Wheel Parameters for encoders & Gobo Index/Speed

There is not a complete list because it is constantly being added to.  In general, as you found, single-name parameters are just their name: Zoom or Pan or Iris.  Multiword things have _ underscores:
gobo_select
beam_fx_select
animation_wheel_mode
edge_blend_2

Things with a / forward slash, replace with a \ backslash:
gobo_index\speed or gobo_ind\spd
animation_ind\spd or animation_index\speed

I did testing for this answer with GitHub - ETCLabs/OSCWidgets: UNOFFICIAL - OSC widgets for your Mac or Windows Desktop so that I could try combinations quickly and easily.  You may find it helpful to open Tab99 Diagnostics and enable incoming and outgoing OSC logging.  Then you can see right away if the name you're trying is working or throws an error.  If you have access to iRFR/aRFR, you can look at Tab99 to see which terms are being sent by the remote device to control each wheel type.

It seems that the underline is no more needed you can use a simple space, also the parameter names are no more case sensitiv.
The backslash is needed because a normal slash is used to separate the OSC containers.