There are three issues:
a) This is a violation of PCR T&Cs.
b) Due to the limited stock of PointBreaks rooms available, making reservations and then selling the nights is considered by many to be detrimental to your fellow PCR members.
c) Selling an award night on Ebay would make it very easy for you to get caught by IHG/PCR. Corporations have security departments that monitor Ebay, and there are ways of getting Ebay to release seller information. Furthermore, you would presumably have to list the date/location of this award reservation--otherwise no one would buy it; it would be trivial for PCR to match you up to this sale even without getting info from Ebay.

If I were in this situation, I would try to change the date of the reservation/appeal for a cancel. If that were not possible, I would contact the hotel as a courtesy to inform them I couldn't use the reservation to make sure I wouldn't have my credit card charged a no-show fee, acknowledging instead that I would forfeit the points.