After doing a little bit of research, it appears the Apollo MSR-2 device is primarily designed to be used with Home Assistant. the MSR-2 runs ESPHome, which is very tightly integrated with Home Assistant. However, there has been some work to allow the use of ESPHome devices directly with Hubitat.
This thread seems to discuss using ESPHome devices directly with Hubitat
The other option would be to run Home Assistant, add the MSR-2 devices to HA, and then use the Home Assistant Device Bridge (HADB) to bring those devices into Hubitat.
As the author of HubDuino (mentioned above by @neonturbo), I would not recommend using HubDuino for this device. HubDuino does not have support for the sensors on the MSR-2 board, and it would take quite a bit of effort to try and reverse engineer everything.