NOT!!!

Same with my SS15. Here in Australia he had 8 days of virtual classes and assessments before they broke for 3 weeks of holidays. 1 day was at our house, the rest at BM's. Day 7 of 8 we receive an email from his maths teacher to let us know that not only has he not submitted one piece of work for maths but he has actually only called in to 1 out of 5 ZOOM (virtual) classes!! They broke for school holidays the next day and since then there have been numerous emails of the same from English, history, science - the list continues. 
BM and DH both naively/ignorantly do the "he is on the computer the whole time, what could he possibley be doing?!" back and forth.....I would love to give them a few suggestions, but have learnt not to waste my breathe. For a moment I go to get worked up and then I remind myself not to care more then either parent does. Ahh the beauty of disengagement! 
I do have to chuckle though, how he thinks he is getting through the next semester (and life) with the same approach is beyond me

My skids are doing their work - at our house, at least. Plus some supplemental stuff that we make a game of. At BM's house, they're focused on gym class, but they're young (1st grade and 4K) so that's OK.  I think they're learning as much as they would have at school. I thank God we're not having to deal with middle or high school kids who would not be as compliant and where the assignments are much more likely to be beyond me.  Having them home all day is enough for me! 

Question is, truly, why do YOU still care?  It's been years of no contact, I understand if for a while you stayed on top of things in case they came back...but this is not healthy Thinkthrice...truly.  Find another hobby.  This can't be good for your mental health.