He is beautiful! Well, handsome.
I had good luck with the DAP diffuser with my SA girl and hers was fairly extreme. I also did a lot of alone training with her. My neighbors used to see me in the hallway a lot! I also got her a walker because it became clear that her breakdown point was at the 4 hour mark. Your boy seems to be on a shorter timeclock but you are experienced, you know what you are doing and you are committed. All good things.