Swap programs are not controlled by a blockchain. SWAP programs are dependent on the integrity of the account owners.

@graphene-swap stole several thousand SWAP.BLURT from me. They treated me like dirt when I contacted them.

Leo-Dex had some sort of swap. LEO stole the funds I tried transferring to HIVE-Engine. The problem isn't unique to @graphene-swap. I suspect that all of the companies in the SWAP business are prone to steal the funds.

Sorry to hear about your loss.

!WINE