Why do you want a Masters degree in either?
An advanced degree in conducting will help you greatly in landing a college job later, or a big-time 6A job. If you don't want that for your career, you're throwing money away to get a fancy paper that you don't really need.
A Masters of Music Education is more geared towards the "why" and "what" of teaching, not the "how" of teaching. It won't necessarily make you any better at your craft.
If you're looking for a Masters degree that will give you more mileage in your later career, get a M.Ed with an admin certificate. If you want to go Fine Arts Admin (or just straight-up administration) eventually, this is how you get there. The other two degrees are nice, but you MUST have your admin cert in order to be a supervisor, and Conducting or M.M.Ed won't help you there.
If you just want the degree because your district pays an extra $5k annually for a Masters degree, go the online route with either a M.Ed or a M.M.Ed and pay about $12-15k. It'll pay for itself in a few years.
That being said, there are tons of great online programs out there as well as in person programs.
For M.Ed Admin, look into UTA and Lamar. For M.M.Ed, try the American Band College, Houston, SFA, or any of the other major Texas music schools. For conducting, some schools even offer distance options for that. You won't go wrong no matter where you decide to go.