Been there, old yeast is the worst. Just toss a pinch in warm water with a little sugar and wait 10 minutes, if it doesnt foam up its dead and you need a new packet.

Your fridge top probably just sits at a steadier temp than you think, and your Denver altitude is messing with your oven proofing way more than you realize. The oven trick works fine, you just need a thermometer in there instead of guessing.

Watched a guy in his 60s clean house at Catan at the Reno Game Center a few months back, same vibe. Comic Kingdom on Wells has a solid Thursday night too if you want another spot to check out.