I can only suggest what I have already suggested really. I see you want different suggestions but it's all I have.
The first nap IMHO needs to be moved later to regulate the WU and first nap time so that it is constant, I see this as helping with nap 2.
It's not clear when you are trying for nap 2:
The second nap I try around 230.
When he does nap it's usually like 215-245.
The earlier WUs can be caused by either the first nap coming too early or the second nap finishing too early leaving a long A time before BT. In your case it can be a combination of both of those things.
If you look back there is a sample routine I gave you - really it is my suggestion and still my suggestion. Getting onto an appropriate and settled routine happens more quickly when you follow the times and LO can learn when to sleep by consistency and habit.