I realize I'm necro-posting here but I may have found a solution to the OP's question. It's a cheap ($35) but versatile MIDI-USB footswitch called the M-VAVE Chocolate BT. (Yes, M-VAVE, not M-Wave.) It sends MIDI over USB-C which, in theory, could control the Catalyst 60 directly without a host interface. It seems to work that way with other MIDI controllable devices.
Here's a complete discussion of what it can do: MIDI "Chocolate" controller with the Mod Dwarf, an introduction - Random - MOD Audio Forum
Here's an Amazon link: https://a.co/d/cCsuanu
It will also take a standard expression pedal as a control input on 1/4".
