I was envisaging a scenario where you made the two separate transactions a few minutes apart, but yes, if the transactions are a few days apart then it becomes far less likely.

Follow up point though: Do people frequently give their exchange deposit address to other people? Given how frequently exchanges sezie coins and lock accounts if these coins have come from any source they deem "unsuitable" or "tainted", I would imagine it is very risky to ask other people to deposit directly to your account if you do not know where those coins are coming from.