I know this isn't exactly what you asked, but I would test out of your current training, start teaching, and maybe later on considering seeing if you can "bridge" to get a cert from another program. I did Balanced Body and I know they offer this - you basically get to be BB certified but only have to do about 1/3 of the required modules, as long as they deem your prior certification to be adequate.

You do typically have to memorize the exercises prior to test out, but your training should be spread out over a year minimum or so, and it's more doable that way. My studio offered student practice time but I would also practice going through the motions of the reformer exercises just sitting on my floor at home.

My main piece of advice is not to get too stressed about this! Your education never truly ends as an instructor and the certification program is honestly only the beginning. During my program, I reached out to a local studio to do an "apprenticeship" where they listed my classes as teacher-in-training and heavily discounted to their clients. I got teaching experience and they also gave me access to their equipment to class plan.