You can open an account even though you do not actually have your RP in hand provided you obtain a letter from your company stating that your RP is in process.

Get this letter and go into any bank - IBQ, CBQ and they should open an account. The RP process takes from a 1 week to couple of months (in some cases) so it is imperative you get a local bank account opened.

You will, in my opinion, incur HSBC charges for withdrawal Qatari Riyals from your US account from the local HSBC ATM's