1. If the coingate staff was serious, the issue would have been resolved by bumping the fee of the first unconfirmed transaction so that it's confirmed. This would make your current unconfirmed transactions invalid, but they would then have to create a new transaction and send you your Bitcoins. Perhaps the person paying out people's withdrawals isn't competent or knowledgeable enough about Bitcoin fees and what's making it worse is that they are creating more transactions using outputs of previously unconfirmed transactions. So, it's now a long chain of unconfirmed transactions.

2.  If you wait it out, the earlier unconfirmed transaction being at 3 sats/byte, I don't think it will be confirmed. It will eventually be dropped out of the mempool (approximately 2 weeks from the time it was broadcasted) and make all the following unconfirmed transactions including your invalid.
Again the coingate team has to create new transactions in order to pay your Bitcoins

I think Option one is what they have to do because it all ends with them having to resend the Bitcoins. After all it was the silly mistake, not yours.