Re: squadrons V
On my HOTAS X (which is pretty much identical to your 4), the buttons have numbers on them. It doesn't help much while in VR, but at least you can familiarize yourself with them beforehand.
Just in case they don't all have numbers and somebody has the same problem, it should be like this:
Stick:
1 - Trigger
2 - middle thumb button
3 - secondary trigger (top right of main trigger)
4 - right thumb button
Throttle:
5 - top thumb button
6 - second thumb button
7 - third thumb button
8 - bottom thumb button
9 - top index button
10 - bottom index button
Base:
11 - left base button
12 - right base button