Safe, probably. For certain levels of safe anyway. It being a
smok brand mod is a point against it off the bat.
The bigger question is has the battery died completely. If LiPo
batteries get too low they’re no longer chargeable. Maybe put it on something heat and fire resistant and let it charge for a few hours. If it charges fine you’re probably good. If it doesn’t take the charge though it’s junk.
The bright side of this is you get to buy a decent
device this time