The fact that he won't allow her room to be cleaned is a problem. Parents insist that a child's room be cleaned, so why should it be any different because you are not her parent. His anger should be directed at her or BM, not at you. 

Personally I would have waited a few more months and then boxed it all up (trash included) and labeled it and put it in the garage. When Spawn moved out and never came back I waited until after the new year (about 6 months) then I went in and boxed it all up (trash, wads of hair, used tampons and pads, poopy underwear, rotted food stuffed in bags) and put it all out in the garage.  DH was also upset with me when I cleaned out the room, but as I told him it’s all boxed up so should Spawn return she can put back everything where she wants it.  It was another six months before Spawn reached out to DH to collect her items. 

Ummm nope.

Doesn't work like that dh.

Sorry he did this to you. It's wrong.

You are the designated scape goat whipping post because you are "safe".

If you dont touch her room, she might just come back.

Denial is not just a river in Egypt.

When SDdnow23 Feral Forger was 18 and graduated high school, she ghosted us, and moved somewhere else without discussion. 7 months I waited, as her funky trashed room got smellier and smellier. One day, Husband said "oh Im going to do a dump run, can I take anything?" And so with HIS blessing, because even though its BOTH our homes, he needed to bless it, I along with SDnow16 then 11 cleared and cleaned for hours. Dressers, chairs, 6 plus bags trash, some 3 bags donate and 3 bins storage of her crap. It was so so gross. He did nothing except take out queen bed. But I made it MINe.

Shes mad still and so freaking what.

Sometimes you have to fight for your top tier position.

Your husband is being ridiculous.  You deserve to live in a clean home that does not have a room that smells.  If your SD didn't clean it, and your DH didn't clean it, then you are entitled to clean it so that you do not have a home that smells and is filled with trash, cobwebs and dirt.

I don't think you should let any of this go.  Your husband isn't the one who should be mad (at you, at least), but YOU should be very annoyed with him for undoing the work you did.  You weren't being malicious; on the contrary, you were packing up things that she likely needs, as well as doing both SD and DH the favor of taking care of the biohazard room.  Tell him that the trash needs to go and that what is staying needs to be put away and kept neat and clean.  If he doesn't want you do do it, and SD isn't around, then he needs to do it and keep up with it.  If he and SD don't want you in her room, then they need to make sure you have no reason to go in there.

I would also let him know that his actions made you feel second best, which isn't where a wife should be. He should be aware that you are not a punching bag or a scapegoat and that the way he handled this was unacceptable.

YSDs room was in a similar state, with rotting food in it when she left. I knew DH would freak out if I went in there and just did my clean up thing. He encouraged her to use trash bags of her stuff from the garage when I did clean-outs formerly instead of making her go through the stuff and make actual decisions about keep/toss/donate. 

So when I saw it was clear she was gone I made sure to get rid of all the rotting food and stuff that could mold. THAT'S it. DH had to be the one to decide to clean the room. I mean, our dresser broke and we needed another one and he would NOT agree to bring hers upstairs for us even though it was pretty much empty (just trash) because she might use it someday (even though she only put trash in it). So I took his cue.

He was actually really upset when we did clean it. It was very filthly and he found gifts he had given her broken or just tossed in a pile. He saw the state of her bedsheets (thrown away, unsalvagable) and realized yes, she had been sleeping on them. It was gross. He felt better after it was cleaned and he is 100% ok with the room re-do that we did on it (my office/guest room). But he had to lead it and I had to be patient.

He should however listed to you and have a rational discussion as an adult in the house, your house too. 

Sounds like he's dealing with some grief/trauma.

After I kicked Killjoy out, it took over a year before I could clean her bathroom.  I tried to go in there several times, but I couldn't breathe, and it wasn't because of any smell.  I felt like my brain was melting.

It's been almost three years, and I'm still struggling.

Luckily my husband was even more freaked out by having anything out of order in Little Idiot's old room than I was. (He has some OCD traits) So I think that overcame any grief he had when I cleaned out the few things she left behind. 

You are a better woman than I am, I'd sneak the trash out on the next trash day! I think the best alternative is to box and bag it all up, trash included, and move it all to the garage or basement.

How on EARTH did your husband let the filth in his daughter's room pile up so high that the stench was making people gag when walking past her door?

If there ever is a next time, OP, have it cleaned by professionals and let your husband pay the bill.

Well I made sure from day one what the house rules were (that SD keep her room neat) and luckily DH is almost an OCD neat freak as me so that area has never been a  huge issue for us but I can tell that what works for me is to do things a little at a time and subltly. If you had just removed a few things (especialy trash) not in fornt of him he probably wouldnt have even noticed. And I do agree with Clove that these men use us as the scapegoat. Hes upset with with daughter but takes it out on you. 

I had the same thing happen with my oldest SD, who is now 21.  She told her dad to leave me, after 8 years together, because she wanted her parents to get back together. He said no,  so she refused to come over anymore, and left her room as it was. After a year of her sisters sharing a small room, while her room remained a shrine - I decided to clean it out and offer it to one of her sisters. I threw away the trash and kept all her mementos in a box in the garage. She took 5 years to come get it, so obviously it didn't mean that much to her. 

When her sisters were offered the room, they declined. DH wasn't happy but didn't say anything. I think they all wanted SD to magically reappear, and refused to accept that she wasn't coming back. I was so tempted to toss her crap when we moved a second time, and had to carry it with us from house to house. Ugh. Dh's are so clueless sometimes about their gross spawn. You have every right to clean her room, as its in YOUR HOME. 

Your mistake was not including him in the clean up or at minimum giving him a choice to participate in it.  Now that it's clean insist on him keeping it that way.  No if and or buts, it's stays clean. When it started to affect the rest of the house, that's when he lost the arguement IMO.  Men can have high levels of tolerance for filth.