I see, that information is helpful. If you think it would be fun and engaging to play that character, then that's fine. There are some other characters engaged in teeth-clenched team work, so as long as he sticks with the others that's also fine. That does sort of render the weakness "doesn't work with others unless he has to" somewhat pointless, and would be better suited as a personality trait. Maybe some sort of weakness relevant to his fighting ability.

I do think that revival once per month is still pretty weak. For reference we have one character who can revive once every three minutes, although I probably won't permit something of that frequency again. You can choose something else if you like. By the way, if you intend for him to be able to use that crossbow, you should include crossbow bolts in his inventory.