I had requested an LOR from an attendign and he wrote it on his practice letterhead. honestly, if u can get it on a hospital letterhead, i say do it. its one of the first thing anyone looks at when they read ur letter: which hospital/university does the author work for. the problem is ur cutting it pretty close. u have less than 5 days to re-ask, upload and release. it may mean that u wont b able to apply on the 16th. which isn't a big deal of course, but just in case ur one of those ppl that wanna apply on the day of.
Thanks for your reply, I decided not to ask, cause in the letter it's clearly stated that his my PD and the same goes below his signature along with the university name, and he's a president of association.