Hello there:)
You know, I wonder if the am nap being so early is in fact reinforcing the EW issue. On days when he does not resettle at 5.30, is he happy or grumpy? Anything different about the previous day - more/less activity? Right now, IMO, his A is on the lower side and he's getting a fair amount of day sleep. It might be worth focusing on ending the EW issue first because that might help to push the am nap later too. And in the mean time, maybe you could cap the am nap, and aim for a longer pm nap? How does that sound? We have moved to a set nap at a much later age than your little fellow but from what I know of others on here - if LO has an EW and it is not possible to settle them, they usually do a quick CN and then stick to am nap at normal time.
When we went through EWs, I would make it a point to keep her in her room in the dark till as close to normal WU as possible. I would then estimate WU based on when I felt she was absolutely up - not drowsy or resting. So A times stayed pretty much the same. I kept at this until the EWs stopped.