Micro Studio Camera 4K G2 - BiDirectional SDI/HDMI 12G

I finally received my Micro Studio Camera 4k G2 and am trying to connect this with a BiDirectional SDI/HDMI 12G Micro Converter to get program return set up, but can't get it to work.
I'm going from the HDMI output of this camera into the HDMI input of the micro converter, and then sending the video feed via the converter's SDI output into my ATEM switcher. And then I'm bringing in the program return from the switcher back into the SDI input of the converter. In theory, this should work since I use the same approach for my BMPCC 6K camera flawlessly; it gets me program return which allows me to shade remotely. However, I haven't had any luck with this new setup. And I've made sure to check the ATEM tally number on both devices, which are set identically.
I'm also trying to avoid using the camera's onboard SDI input and output because (a) it uses two mini/micro SDIs (which I don't have) and (b) it's not cheap to get a mini/micro-to-regular-size-SDI-cable. What else am I missing? Or is it something on Blackmagic's end that could be fixed with a potential firmware update?
I'm going from the HDMI output of this camera into the HDMI input of the micro converter, and then sending the video feed via the converter's SDI output into my ATEM switcher. And then I'm bringing in the program return from the switcher back into the SDI input of the converter. In theory, this should work since I use the same approach for my BMPCC 6K camera flawlessly; it gets me program return which allows me to shade remotely. However, I haven't had any luck with this new setup. And I've made sure to check the ATEM tally number on both devices, which are set identically.
I'm also trying to avoid using the camera's onboard SDI input and output because (a) it uses two mini/micro SDIs (which I don't have) and (b) it's not cheap to get a mini/micro-to-regular-size-SDI-cable. What else am I missing? Or is it something on Blackmagic's end that could be fixed with a potential firmware update?