As long their is no open wounds then it shouldn't be too dangerous.and event though axolotls do have regenerative powers,its possible that the hand wont heal properly if the bone is still attached.
I would recommend taking it to vet to get their opinion.
P.s. don't try to amputate the broken limb
Hope your axie gets better though !
Hope this helps
Just leave him be - Axolotls are fantastic healers, and it should heal up on its own as long as the water is kept very clean (0 ammonia, 0 nitrite and less than 40ppm nitrate) and your temperature correct.
My axie is acting woerd he was a rescue as stated in a different post he got better and now seems to be deteriorating again...again all tank conditions are OK and as should be. He seems to have some black dapple like pattern under his bottom lip? Is that normal? And his two back feet have a little wierd growth? Almost? Tiny tiny tiny lump. His capillaries in his feathers also appear darker and more visible. Any help would be appreciated