All your Busses in your pic are Mono. Tracks routed to a mono-bus and busses routed to a mono-bus (your far right drums-bus also is mono) don´t and can´t have a panner.
The last drum-bus has a panner because it´s routed to the stereo-out.
If you want to pan your toms and cymbal tracks make the tom and cymbal-bus stereo as well as the drums-bus.
Make those busses stereo by clicking on the small circle above the track name.
Send all of your Mono and Stereo Drum Tracks to a Stereo Drum Buss. You can Pan each of your Mono Drum tracks in the mixer…Panner Balancer is for Stereo…you can’t Pan Stereo so the Pan Balancer will adjust levels on the L and R seperately to approximate Panning placement