Hadron 640R support is in beta. You can request a custom invoice for the adapter at https://modalai.com/contact
We have no experience with Herelink. The modems we have support for MVX, Doodle Labs, Cellular and Wifi
You cannot use HD Zero to send video from VOXL 2
The software is all open, so if you need to send custom gimbal commands you may need to update the software
VIO cameras need to be fixed mounted with the VOXL 2 and cannot be on a gimbal