I'm not an expert, but based on traits from the link I put up earlier and from a few other sources, I'm pretty sure this guy is a Halmahera Indonesian BTS. The black forelegs mean he is definitely not a northern or eastern of the Australian species.
He definitely needs higher humidity than he had before. They probably assumed he was one of the Australian species or didn't know there were different ones and followed a generic care guide and had him in too low humidity the whole time they had him to cause him to lose those toes. Poor guy.
I second Reptile Mountain TV as a source for skink info, I'm using his videos while I research before getting my own BTS, though I am aiming for a northern. His information is all very good.
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