I'm perturbed. You just funded that. Which means that prior to yesterday, you did not have a cold wallet at all. That also leads me to consider you probably haven't secured the cold wallet properly.
You also claimed to have 4-figures of BTC before, then 3-figures. That cold wallet barely comes to 100 BTC.
I will hold my promise though, and remove the negative trust.
DC, but what's wrong with holding money in fiat? Having a big bankroll is having a big bankroll and if you're worried about how they secured their bitcoin wallet, perhaps they were actually safer when their money was in a traditional bank (FDIC in USA, or whatever equivalent). Anyway, I agree that they should sign a message from the address. Just suggesting that these guys seem to be step-by-step, doing the right thing, and this situation, as it stand now, is much better than things looked a few days ago when everyone assumed they were long gone.
Looking forward to hearing back from yoler that he got he withdrawal.