By battery pin I assume you mean the connection between your tank and the tube mod that contains the internal battery, that is know as the 510 connection. Not at all uncommon for it to be a little wet with
juice. Now if it was dripping wet to the point juice may have entered the tube mod that could damage the circuit board or the internal battery. If that has happened its probably beyond economical repair.
You didn’t describe any event that would account for enough moisture to brick your mod, so I don’t suspect liquid in the mod is the issue.
Not clear on the order of things though, was it working when you put it on top of the stove and was no longer working when you took it off the top of the stove? How hot do you think it got sitting up there? I assume you didn’t expose it to direct heat from a burner, if you did then I think you have your answer. My assumption was it was receiving indirect heat just from being in close proximity to the stove.
Are you from the US and does stove mean cooking stove? Sorry but language differences on an international forum can create it’s own set of problems.