A regulated US exchange like Gemini has FDIC insurance on USD held in the account (but not BTC). So the risk of losing funds - as long as they’re in USD - from a hack or theft is near zero.
The greater risk may be that a government attempts to seize the funds if they are threatened by Nu. For that reason, @DHume should give consideration to how the BTC would be transferred from FLOT to himself with the greatest amount of anonymity possible.
@DHume I like your proposal. As long as the asset is reasonably liquid (and I think BKS will be very soon), Nu has nothing to lose by accepting an offer with >100% collateral. If we can reliably convert a higher portion of Tier 4 to USD our network will be stronger for it. I will support your motion for the full $50,000.