They are misinformed about "liability". If they knowingly avoided helping in the marina you are berthed, they are liable (exception loss of life/limb). I gave my Mariana written permission to do what they could. They know where I keep extras lines.
Leave them for poor service.
Jim...PS: Even Wally mart is liable for their free parking lot.
I do not believe this is correct. If they do not have a staff member with some kind of qualifications to do something like this, then they are best to call a professional. If they were to send an unqualified person and that person was injured, both the hotel (marina) and the owner become liable.
No marina is duty bound to care for equipment on their premises. Life and limb, surely, but not otherwise.
"Even Wally mart is liable for their free parking lot", Not hardly! Someone runs into your car in their lot, they say, "Not our responsibility.", and it is so posted EVERYWHERE around that lot.