There is no way rich grandparents lose custudy over impoverished father. Even if my miracle he won, they would at the very least have court mandated visitation rights. The only explainable reason about why his grandparents are not in his life is because they don't want to be.
Hopefully you're right, we already have too much coincidence with the whole Maya is dating Josy thing.
IF it all takes place in some hybrid USA/Sweden like country and the same rules apply then Nope and nope, access to the child for grandparents is determined by 1 thing and 1 thing only - established prior relationship and even that happend quite recently in 2015/2016'ish, the right to sue that is if a prior relationship has been established. And despite what movies might let us all believe, it takes a shitton for a court to take the child away from his biological father, no matter how rich the grandparents on the mothers side are.
Whats interessting in that context however, is that when Lynette went to the hospital with Neil - she was obvious awake and therefore in charge of who has access to her. Most of all complications during child birth come from bloodloss, IF that was the case, and she lost consciousness shortly after, the right to decide all future steps regarding her health would move over to her closest relative ( unless a power of attorney has been issued, which given that she is 19? is highly unlikely ) - in her case, her parents. IF, and yea im aware those are a lot of "if's" she would've slipped into a coma, her parents could block any and all access for neil. And IF ( yea yea ) she lets say woke up after 3'ish months, a loss of memory would not be that unlikely. Her parents couldve tucked her away at a private facility and then told her some lie. Neil would have to sue for his childs access to get any information, and who the hell does that?
My like supah-supah happy ending wish would be : MC continues reading her diary and then he finds a line where Lynette is pissed and writes "but im a burgmeister, we dont run away from problems, we face them!" and then the MC runs out of his room, yelling "rusty, rusty, rusty" and then he finds out rusty is his cousin, and his mom ( rustys aunt ) is alive and well ... and yea i know ... im a crazy person.