Day 3 Update:
the mag reacted fine to Sufathiazole. I'm sorry I didn't shoot any pictures because it's so big a job to prepare fresh saltwater, change water and add antibiotics and bleach the disposed water ;-) Now I'm like going double gym in the evening.
my biggest concern: the cut by its mouth heals--best news so far and I'll take some pictures of the scar. I don't know how it came but I should've taken an immediate action. It didn't heal by itself for like 5 days and then it went down very fast. now the cut heals and its size triples and reacts to light change. these are good signs.
the bad sign: the mouth is still loose--this is the worst version. IMO a mag's mouth can be swollen big, gaping but if it goes loose, it's really sick.