Welcome to planDisney, Marlie!
We're so happy to hear that you're wanting to go to
Hollywood Studios for an After Hours Event! An After Hours Event at Hollywood Studios is on my bucket list, so I hope you go and enjoy this incredibly magical event for the both of us! YAY!
I had the privilege of chatting with a lovely Cast Member, Arista, about your question, Marlie! I wanted to make sure you got the most accurate information about current policy. Arista stated that, "Yes, you can book dining reservations with just a special event ticket, you do just want to make sure that the reservation is within the period that you are allowed in. If you have an After Hours tickets that allows you to enter as early as 7:00PM, you would have to make sure that any dining reservation is made at 7:00PM or later." Your plan to make a 7:35PM
Roundup Rodeo BBQ reservation (great choice, by the way, this is my little family's new favorite restaurant at Disney World) will work perfectly! That should give you plenty of time to get back to the restaurant after you arrive if you are through security and getting into the park right at 7:00PM.
If you are unable to secure a reservation, you can always join the Walk-Up Waitlist for the restaurant once you are within Hollywood Studios. This would be a good backup option for you just in case!
If you have any additional questions, we hope you'll visit us again here at planDisney!
Happy trails,
Allyn