thats a tricky one, you could try posting in the DISabilities forum for more advice.
I can imagine two being croweded in the room but three would fill the room space!!
you could always leave one outside of your room, aslong as you take the key and its tucked away out of the possbility of rain i doubt there would be a problem. best thing would be to contact your resort and discuss this with the hotel directly as they probably deal with these types of enquiries all the time and would be able to point out where to place it for maxmum security and charge.
hope you have a fantastic trip!