I am not sure about the fact that synced Bitcoin Core wallet's data is useless for Bitcoin Cash one. There is probably a command line option to verify last couple of blocks and it will discard the invalid (Bitcoin Core after fork) ones.
It should be useless.A totally different chain remember ?
This was a massive free lunch for BTC holders by the way.
I did the whole BCH-claiming operation on Saturday and earned myself a nice $950 bonus only from having held 1.1 BTC in my wallet when the fork happened.
Epic.
The same would be valued at $50 in the coming weeks after the big dump.You did the right thing by selling when the price was still right.