No where in the information that is made available to crew at my airline states that we are not able to take up issues with the hotel directly.
I have already filled in a "Feedback Report" regarding the property which will be read by the Hotel Contracts Manager. However I doubt much will come of that, as we have numerous hotel issues that have been going on for many months which have had nothing down, despite multiple reports from many a crew member.
As for asking about the benefit, maybe not the best thing to have done, but to have been given it the last 15 or so stays at the property, having been checked in by some very helpful staff, including the front desk manager, to have this experience with the particular person checking me in to be so flippant in terms of even adding my PC number to the room folio, I did not really think there was anything to loose.