What an absolutely beautiful bunny. As long as a rabbit is trying to live, I usually support the fight. They can be incredibly resilient little things!
You're doing what I would do in this situation: clean it out and give him sanitary and nutritional support. Once he's healing, when the doe doesn't smell death on him, you may be able to put him back with her to nurse, but he looks like he's maybe 2-3 weeks so feeding him by dropper/syringe is at least doable.
Something I'd do whether or not he back in with mom, is to make sure he has hay, a few pellets, and some of mom's poops in his box with him, to encourage him to start nibbling on something other than milk. He's nearly certainly going to be one that is weaned earlier than normal, and you want his little gut to get primed as early as possible.
I am wondering how or why the whole litter had this problem with fly strike? I thought fly strike happened when there was a significant problem with unsanitary/wet condition, or an existing wound in the animal that gets infested. (I am not accusing you of neglect - you obviously pay attention to and care for your rabbits. I am just curious since it's not a problem I've ever dealt with.)
Nice job pulling him through so far!