Scheduling time to see DGPs

[thetwocultures]

I work PT evenings and up to now I would go to my DParents once a week with DS and head to work around 4ish and they would drop him off home to OH an hour before bedtime.
My DM doesn't work but my DDad does so he would usually see him for a couple of hours or so.

My DD has recently started a new job which will mean that he would not be able to see DS through the week as he would finish just before or around the time DS has to be dropped off home.
Originally we arranged to see my DPs through the week as weekends are time for my OH and DS to spend time together as usually me and OH miss each other through the week due to the working hours.

If anyone read my previous posts there's a huge backstory here but basically my DPs and my OH dislike and do not talk to each other at all. - extremely complicated big and small faults on both sides probably bigger on my DPs. It's not getting resolved anytime soon or ever.

I'm trying to rearrange a better time to go see them every week so my DD sees him too. OH has said that we can do Saturday 8am and be home for 12 (including 30min drive one way) which will massively cut down on the time we'd spend there before, if we run late as it would mean early starts by the time we are done travelling etc we might get just over 2hours or so. And he is not willing to compromise on the time he gets to see DS.
My DPs suggested that DS could stay over every Friday and they would bring him back Saturday morning which I thought wasn't the worst idea as it would just mean OH won't see him for an hour or two Friday and then he'd be back before OH finishes work Saturday and we've got the weekends together. OH doesn't want to hear it, he said he doesn't trust them and doesn't trust they'll put him to bed on time etc. (IDK why) He said the only way he'll compromise is to keep it 8-12 3 Saturday's a month and 1 night he can sleep over but only if I sleep over there too as he doesn't trust them....

It wouldn't make a difference if I stay over or not as I'm at work when DS goes to bed anyway but he's adamant on it.
I know my parents might be sad/hurt about it as my DMiL and DFiL see DS a bit more as they babysit him 4 days a week in between me going to work and OH coming back and now their time is getting cut even more. But I know we need to prioritise what's the best for us as a family.

I just need a bit of guidance/opinions in terms of what is or isn't reasonable here.

My idea was to let DS sleep over 1 or 2 times a month and have him brought back for 11 on Sat and then see them 8-12 on Saturdays when he is not sleeping over.
OH says 3 times a month 8-12 on a Saturday and 1 sleep over with me staying over there as well (-which I don't want to do).

I know it's a stupid issue but any advice would be appreciated!

[SpareASquare]

I don't know the backstory but get that your DP is pissed at your parents. He is clearly about hitting them where it hurts and using your child to punish them.
No matter who is at fault, it's a pretty pathetic thing to do