No kidding--that's way too much money to be leaving it on any crypto exchange, even if it's one with an excellent reputation.  Cryptsy had a similar reputation right before they absconded with all of their customers' funds, and I'm sure there are at least a dozen other exchanges that have pulled the same crap over the years that I'm just not recalling at the moment.

The KYC requirement probably has to do with the amounts in question, because smaller traders don't usually have problems with Kucoin or have to submit their ID documentation for any reason.  Hopefully OP will get it all straightened out--and I suspect he will, because I don't think Kucoin is a scam exchange and they're above average as far as their customer support goes.  And OP, it would be nice if you kept the community updated on this.