Thanks for the question. If you are able to feel your glutes engage during yoga and strength I would make the assumption that things are firing normally. As far as getting your glutes to engage when pedaling there are a few things to keep in mind to increase engagement and efficiency. One is definitely fit. If your saddle is too far forward or too high it will be difficult to get good glute involvement. Check to see if you can get to the bottom of your stroke without having to toe down. If you have had a good bike fit, I would trust that to start and focus on these next things. First, be sure that you are not sliding forward on the saddle. Rather, slide back a little bit and see if this helps. Second, drop your heels on your downstroke so that they are flat or level with the ground, focus on driving through your heel. Also, slow your cadence down and see if you can get things connected.
Give these a go and see if you can find your glutes again.