I can only see a couple of things that could have happened here.
1.) The multipool did not update their wallet which is why there would be so many coins to send as it would have only been them on that fork of the blockchain.
2.) You have put your Feathercoin address into the a different coins output address on the multipool.
Either way its worth raising with the multipool themselves. And ask for the details of the tx where the coins were sent.
I don’t think the coins were ever sent on the real Feathercoin network.
Can I ask where you saw the details of the transactions that you are posting here.