Don't quote me saying you can or can't, I think it would withstand the weight but something to think about; What if a wind comes by and catches under that awning? The awnings we install from the factory are built to be able to withstand that and are attached to a mounted sidewall. If something like that were to happen on your slide it could knock your slide out of cant.
PLEASE do not send questions via Profile comments or Private Message, my inbox fills up too quickly. Post questions in the forum as a new thread so that other users can benefit from the answers. Use Private Messages for sensitive information only (VIN, Contact info or things you do not want the public to see).