Compatibility Report

I had refunded the game, I frankly was not expecting a response. Repurchased it, although with no sales at this time.
Thanks for telling me the correct way to use the +vrclient and +openxr, added to my notes.
Ran the game with proton experimental bleeding-edge in VR via Steam Link with these launch options, and here is the result (zipped, because it became too big to upload):

steam-589040.zip

On successful run here the game is using IVRInput. In your log it doesn't use that at all, after querying some controller properties. I am guessing the game just supports some limited set of controller models and doesn't attempt to use the ones it doesn't know. I cannot establish that for sure without reproducing your exact setup but it looks likely (and we saw the similar cases already). Probably the best bet is to try to map the controllers in ALVR (IIRC that worked last time with another game)?

Yes, ALVR has options to map the controllers to a number of different controllers: Rift S Touch, Quest 2 Touch, Quest 3 Touch Plus, Quest Pro, Pico 4, Valve Index [knuckles], Vive Wands, Vive Trackers and Custom. I'll do some attempts emulating these controllers.

Last time we did that was with X: Rebirth VR. Using Vive Wands and also Valve Index worked for the game. I'll start with these.

BTW, if you guys would be looking for someone to test some, you know, VR hardware or something, I've already been dedicating all my free time to VR testing and I live in Poland.

The game has the following controller binding files in its install dir:

bindings_vive_cosmos.json
bindings_oculus_touch.json
binding_holographic_hmd.json
bindings_knuckles.json
bindings_holographic_controller.json
bindings_vive_cosmos_controller.json
binding_vive_pro.json
binding_vive_tracker_camera.json
binding_vive.json
bindings_vive_controller.json
binding_rift.json

Those are probably the ones it is supposed to support.

Tried emulating the Valve Index knuckles, no luck. I know the Index knuckles emulation is working because it shows the controllers in the VR interface and also the buttons were moving in VR when pressed.

However when I start the game the symptom is the very same of the video I recorded. The hands appear in the ground and no interaction is possible.

Here are the logs. For completeness, I even tried with SteamVR stable and the current SteamVR beta that I am using most of the time.

(I have also tried emulating the Vive Wands but it seems this emulation in ALVR is currently broken. will try the rift too)

steam-589040-valveknuckles-steamvr-stable.zip

steam-589040-valveknuckles-steamvr-beta.zip

No emulation seems to work, tried various combinations of different emulation modes in the two settings that are related to this in ALVR. All results were the same, the hands would appear immobile in the ground. Also tried WiVRn and the difference there is that the translucent hands don't even appear.

Anything else that can be done with this issue? I've run WiVRn (where the hands don't even appear) and it has shown this info about the game:

 INFO [client_loop] Client 6 connected
 INFO [ipc_handle_instance_describe_client] Client info:
	id: 6
	application_name: 'wineopenxr test instance'
	pid: 102492
	extensions:
		ext_hand_tracking_enabled: false
		ext_hand_tracking_data_source_enabled: false
		ext_eye_gaze_interaction_enabled: false
		ext_hand_interaction_enabled: false
		htc_facial_tracking_enabled: false
		fb_body_tracking_enabled: false
		meta_body_tracking_full_body_enabled: false
		meta_body_tracking_calibration_enabled: false
		fb_face_tracking2_enabled: false

Maybe there is some technical info I can use to create a new bug report on SteamVR, ALVR or WiVRn?

It looks most likely that the game still doesn't recognize something about the controller the way it is faked. I don't know what exactly unfortunately, that needs some debugging ideally with the setup which reproduces the issue. Might look at some moment to precisely see what is it querying and which parameters / names are important, but not right now at least. Maybe it makes sense to report to ALVR either way, what if someone with appropriate setup is interested to look from that side (while if that can be fixed at all outside of the game that would be more likely controller or headset faking details).