I haven’t tried yet for 5.5 but its on my list for early next year to take a look at. Was working in 5.4. It’s been a minute since I messed with pogo pins, and was a pain in the butt to get working. Page 17 of their developer guide lays out what pins are mapped to what.
https://dl.vive.com/Tracker/Guideline/HTC_Vive_Tracker_Developer_Guidelines_v1.3.pdf
One of the biggest problems I had was that OpenXR expects inputs like buttons and triggers on a handheld “role” so it wouldn’t work while using a controller. So they need to be turned off for OpenXR to see the input and you need to map your tracker role to a hand left or right.