Ultrasonic cleaners for delicate parts?

Group,

The homing switches on my mill are failing sporadically, and a single
switch is $327.00. I can't disassemble the switch without digging
the glue out of the back (where the wire exits), so, I'm wondering if
cleaning them in an ultrasonic tank will harm them?

The switch is quite small, and appears simple, but the price suggests
otherwise. The switch is cylindrical, two wire, and looks to have a
glass plunger about 1/16" dia. Must be some kinda super precision
unit. The machine uses the switch to home/set limit, and to
calculate backlash upon initialization.

The machine was quite dusty/greasy when I took delivery, and I think
this dust/grease has gotten inside the switches.

Is ultrasonic cleaning ok for such delicate electrical devices?

Thanks,

Patrick