That's not obviously the sunk cost fallacy. The $180 is gone, the only relevant question is "how much more do I have to put in before I win?"

If you think that amount is more than $180 and you continue to play, because you've already spent $180, that's the sunk cost fallacy.

If you think that amount is less than $180, continuing to play is (to a first approximation) the correct decision. You can either get a tablet for less than $180 here, or for $180 in a shop; also, you've just burned $180. If you were to stop playing, in order to avoid committing the sunk cost fallacy, that would be the sunk cost fallacy fallacy.

It seems likely to me that the mistake being made, after spending $180, is the same mistake that causes people to start playing in the first place. (I couldn't say precisely what mistake that is.)

You're right, except in the case that someone who has spent >$180 in bids so far might actually realize what a horrible scam this is, and might see that it would be irrational for a person to start bidding at this point, and yet chose to go on because they've already spent $180 and want to at least get something in return for it.

In this case, the sunk cost fallacy is what would drive them to keep going, even once they've realized what a terrible trap this "auction" is.