Well, I have to be honest here, your inclinations are probably right
I will openly admit that I have in fact cheated on my ex (no, I'm not proud to admit that, but honest)
So that being said, I can recognize the signs. The glitter, the restricted phone times, peculiar ringtone in the background followed by an answer, the deleted history on gps, the fact that your husband was in fact at a hotel the exact distance as calculated. If hotel stays aren't typical of his job requirements, then why was he there.
I don't know what he does for a living, but would that be the type of place you'd find a woman wearing glitter. Can you access his phone, does he now lock it, did he always. He's being secretive and slightly defensive, if he didn't typically buy random gifts for you then that's more than likely his guilty conscience talking, he may think you're catching his game a little by asking questions that are related and pinpoint what he is doing. So in his head, he probably thinks you know something's up and trying to cover tracks and "winning" your confidence back with a gift, that could also be an excuse for extra mileage if he thinks you're checking on that. And the other obvious sign is the lack of ejaculate, if it's the same as it "normally' was/is when he hasn't "disappeared" then the age excuse is bull$#!t as well.
If you'd like, feel free to send me a PM. If there's more details you may want help "ironing out" I may be able to help you with that.
This doesn't mean your marriage is over, I've been the mischievous one in a relationship and I can say without a doubt, it's not something I'd do again. I lost everything, and sometimes a wake-up call is all he may need to straighten out.