Make sure you wipe down the surfaces with IPA or similar to remove dust and grease.
I’d bring it inside to somewhere warm also. You’ll get much better result with the glue.
It will likely go hard pretty quick but I’d check what the time to full strength is before any testing. It might be as long as 48h. Normally they quote at 25C and I’m guessing where you are working is cooler than that. 15C could be twice as long!
What glue did the use in the end. Based on my experience I’d have gone with UHU Endfest. It came out best in tests I ran at work. I wouldn’t go for an MMA if the manufacture recommends epoxy. You might be ok but you would not have an appreciation of why they made the recommendation in the first instance. Epoxy is typically stronger but that’s a massive generalisation.