you don't need to ask the scammer if he is trying to scam you . simply look at the evidence.
besides the circumstantial evidence that I have already stated then look at the item he is trying to sell.
you have a rusted out tobacco box that has the patina of being over 30 years old. within this tin you have an assortment of valuable coins in 2x2s and sleeves.
these 2x2's have no signs of wear on the tabs, the 1st place to get damage when handled and/or stored in a box.
the plastic sleeve that the florin is in looks almost new with no signs of yellowing or cloudiness.
the silver papal medallion has not reacted at all with the tin. my experience has taught me coins in tobacco tins go bad, quick, as they react with the metal the tin is made of.
so to accept this seller is not a scam artist you would have to accept that someone knew enough about collecting to recently put the valuable coins in good storage media but then didn't think enough about the coins to store them in anything other than a crappy rusty old tobacco tin
which turns out was a great move because it ensured that the coins have kept in better condition than other collections I have found in files loaded with the proper 2x2 sheets less than 10 years old.
that was my investigation, I don't trust any one I don't know on ebay so why bother asking him?