hey everyone! Marvin (my tortoise) is doing a lot better now. he eats every day and is extremely active. he lets me hold him and pet him when i need to. i am cleaning it with betadine and using a spray anti septic after i use a warm towel to clean off the betadine. i soak him once a day and i also keep him warm and quiet with plenty of food. but does his shell grow back? or will those scutes be gone forever?All of the advice you've been given is good stuff. There really is no 'correct' way. It's usually a matter of opinion. Here's what I would do if it were my tortoise.
I love your habitat! You've done a great job making a nice big area for the tortoise. I would go buy some plants in 6" pots and place them around inside the enclosure (still in the pots to keep them up and away from the tortoise). The tortoise might knock them over and eat the plant anyway, but maybe if you dig the pot down into the substrate it will give it more stability.
I would not cover the wound, but rather allow it to dry out. I might put Neosporin on it the first day, but nothing after that. Just let it dry out. Keeping the tortoise warm and quiet will help him get over the stress of the attack. I worry that a constant temp of 80-90 might be a little too much. I fell there should be a spot where he can cool down a bit if he wants too. Also, I would turn off the mist at night. In fact, (now this is MY opinion) I feel that tortoise is big enough now that he doesn't need the mist anymore.
You seem like you're a caring animal keeper, and you're doing great by your tortoise. Please keep us in the loop on how the tortoise is getting along.