Hahahaha!  "get my BTC back".  Good one.  

Those are gone.  The good news is that the total amounts to about only 15 cents (US).  The Mastercoin protocol doesn't control whether or not you can put transactions (even corrupt bad ones) on the bitcoin blockchain.  The bitcoin blockchain doesn't know those addresses are without Mastercoin - and doesn't care either.  The mastercoin parsers will notice those addresses are not funded with MSC - and reject the offer.  However, the corrupt offer will still exist on the blockchain and the bitcoin used to form the corrupt offer will still be consumed in forming the bad offer.  Get it?