As a hotel front desk supervisor, I can tell you that you will not get the GST back. With prepaid reservations through internet companies like Expedia, Priceline and Hotwire, the financial transaction was made between you and those companies and NOT between you and the hotel. These online agencies are American companies, as such you will not have been charged the GST. The only way you will be charged GST is if the transaction was made between you and the hotel in Canada, i.e. you booked a room and paid the hotel directly for it.

Besides, the contract between Hotwire and all the hotels it books is confidential, and I can tell you 101% that the hotel will not show you the breakdown of the cost. These rooms are sold to Hotwire at heavily discounted rates, and Hotwire and the hotel have agreed that the customer must not see this exclusive rate. Otherwise you would see that Hotwire is making a fat profit from you!