Caseta ELV+/Pro with low-voltage MR16 LEDs

I have a light fixture with two groups of 8 12V MR16 bulbs each on separate dimmers. I bought both a Caseta ELV+ dimmer since that seemed like the right one, and a Caseta Pro dimmer, since some threads here say it can have better compatibility.

Installed them on the two circuits. Group 1 worked great, Group 2 flickered. I thought, OK, apparently the ELV+ dimmer works and the Pro dimmer does not. Swapped them. Group 1 is fine with either dimmer, Group 2 kept flickering.

Bulbs are all the same type (Hyperikon 161070105 MR16 LED 7-watt, 2700K, CRI90+, Dimmable). I tried changing the phase; that made the flicker almost go away, but the dimming became a blinking mess, so not a solution. I tried adding 2 old halogens to each group to add load (6 LED/2 halogen), that did not help.

The only other thing I can think of is the 12V transformers. I can't see the transformers, they're buried in the hard-to-open ceiling-mounted fixture.

Is it worth trying other light bulbs? Not sure I want to go to Sanaas at 3x the price.

Any thought on the chances that if I swap the dimmers for Caseta on/off switches, the flickering will go away?

Any further testing one can do with the transformers?

I've read other threads and understand 12V MR16s are difficult. Just want to see if I'm missing something here.

Thanks!

If the same bulbs work in the first group regardless of the dimmer type then I would say something in the second group. Same type of bulbs (Hypericon) so trying an other brand in for the second group might help but doesn't seems like that would be the problem.
Using a Caseta switch probably work without flickering however I assume you need the dimming feature.
Maybe try to install bulbs one-by-one to see if a certain lightfixture (transformer) trigger the problem. In that case you still should get access to the transformer to be able to replace it.