OP is referring to the curious death of the founder of QuadrigaCX who supposedly was the only one with the keys to cold storage. This does not apply to 0x-base

OP is referring to the curious death of the founder of QuadrigaCX who supposedly was the only one with the keys to cold storage. This does not apply to 0x-based exchanges at all - it's a nuncustodial solution, meaning you can put orders without depositing coins and ensure they are only transferred out of your wallet as part of a correctly executed trade, atomically.