Custody situation we have picked sides

We have mutual friends that are divorced with multiple children. They have 50/50 custody. It's hard for us because we love them both but we are finding ourselves picking sides.

Their situation is their children are none verbal autistic. They are in special school because of it. The one parent is stay at home. The other had to find affordable housing outside the district so they cannot have the children during the week. The working parent also pays for the home for the stay at home parent for the children to live in. The working parent works nights.

The situation is the parent that is at home with the kids gets to count their time even when the kids are at school. The working parent is always calling in sick to work because they have to stay home if the kids are sick. Also they call in if they has to make up if the stay home parents hours are not 50/50. So the stay home parent counts when the kids are sleeping and school.

The parent outside the home works nights and gets off work to get all the kids off to school. Then greets them when they get off the bus. They do all the cooking and meals for the kids too. Then they leave for work at night. They never get enough sleep and are super stressed about being fired for too much missed work.

The parent inside the home has calculated everything down to minutes of time with the kids. They have emptied the bills accounts to travel. They have called me for favors to watch the kids. I refuse to help them. Imo if they had a job when their kids were in school it would be different. If they were understanding of how they have taken advantage of the system and tried to make it equal I would seek helping them. That isn't the case at all. I'm forced to pick sides in this situation and will help one parent but not the other as they are so needing of help I can't possibly help both frequently.

Can someone explain to me how 50/50 works if the kids are all in school? Wouldn't just the time not in school be split?