Yep, that’s what I was expecting when I asked you about errors. This is an attribute that we just added to Z2M in the current month’s release since it was missing. It turns out that while the specs say it should be included in the VZM31, it’s currently missing on that device. I have a branch removing it temporarily from the VZM31 that I’ll push up shortly. I’ll link it here when it’s ready.
Edit: https://github.com/Koenkk/zigbee-herdsman-converters/pull/9756 is the change. Once that’s merged in, if you switch to the Z2M Edge/dev branch, and then reconfigure the device, it should set itself up correctly and fix the reporting and the multiplier setup. Since Z2M releases once a month, the next production release that will have this fix in it will be released on September 1st, 2025.