If he’s not eating enough, you need to force-feed critical care. It can seem like you’re being a bad owner, forcing your rabbit to do something it doesn’t want, but that small window of (not really) harmful suffering is what’s required for a full recovery.
Although rabbits flail when restrained, they typically won’t actually hurt themselves unless they fall off of something, or they ram into a nearby object at high speeds. If it’s simply you, grabbing and gently restraining them (I trust you know the difference between a firm grip and one that would break bones), they will not harm themselves.
Since he is eating some things on his own, that’s good; however, you believe overall nutrient consumption is low, or your rabbit is losing weight and is clearly still hungry, you need to force feed CC.
Alternatively, you can make a pellet mush and see if this is more enticing to your rabbit. You soak pellets in water to create it.
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.