When are you going? We can test it out the week after next to see and try to report back (unless someone here or on Youtube tests it out first), but I am pretty confident that they allow anyone as long as you have a valid ticket. There were some Youtubers last year who also used the entrance with no issues as well last year.
I'll be down there Oct 6th through 15th and hitting two parties (Sun Oct 8th and Tue Oct 10th) and my stay at the Grand is check in on Oct 8th and check out on Wed the 11th.
More that I think about it I actually do prefer DLH. I forgot the Grand and their valet parking. I much prefer how fast I can get in and out at the DLH and if I need to run down to the car for any reason. Also the bell hop at DLH has always been really quick (five minutes or less) and the Grand for some reason gets REALLY busy at times...