this might be problematic because travel time in the mail system can vary quite a bit and the timing would have to be pretty exact to deliver it before your brother leaves. Also both the hotel and the shipper might have an issue with delivering to a hotel. You can try though, cant hurt to ask.
If its a major city, you might be better off asking geekhackers if anyone lives anywhere near the hotel where your brother is planning to stay at, and asking them if they'd mind taking delivery of the package.