Does this look purposefully inflicted?

When my ex and I were together the very few times he would try to change my son’s diaper he would wind up pushing really hard with this thumbs (right about where that bruise is) to make him sit still.

Now my son sees him once a week for 5 hours, and he keeps coming home with this bruise.

I can’t decide if maybe it’s just his waistband or if I should be concerned that his “dad” is being rough with him again.

I only let him see our son if his mom is present. But she’s trying to help him get full custody (even though he’s never been alone with him longer than an hour or two) and I don’t think she would say anything if he WAS being rough.

Idk what to think but it’s really concerning. My son is REALLY difficult to change these days because he’s so wiggly and I can just imagine him being pinned down like he used to or pushed around.

Edit *****

The picture is blurry because he was wiggling. It is a bruise, but I see /that it looks like a rash in the picture.

He’s never alone with my son, his mom or dad is alway there. And they would step in and stop him, they just wouldn’t tell me or the courts about it. :(

We have trial in March and I’m going to request a court appointed supervisor.