Vizconnect and HTC Vive Trackers

[Vaquero]

Hi!
For a study, we wanted to replicate the full body tracking with IK that you demonstrate in this short clip: https://youtu.be/Hf-oRZF5mGw
Unfortunately, in Vizconnect I couldn't find a way to add the HTC Vive trackers, because there are only entries for the SteamVR HMD and the SteamVR Controllers, which both work. I tried those entries to connect to the extra trackers with different IDs, but to no avail.
On the other hand, steamvr.getTrackerList() lists the trackers when the script is running. But I would need them in Vizconnect to set up the IK for the avatar, right?
Since you show off a running demo, can you please tell me what need's to be done to be able to use the extra HTC Vive trackers?