I’m having the same problem / run into the same limitation as talked about here:
Can I base privacy rules on child records?
Privacy Rules problem (Rules that use “This Things X’s Y” can’t grant search access right now)
Basically, what I intended to do is set a rule like: Current Users’s User Role’s Project contains this Project AND Current Users’s User Role’s Role Type contains Admin → Can view & edit etc. This is apparently not possible and each ‘Thing’ would need to have a field with ‘User’ represented in it.
does that make sense now?