Mr Jingles enters, runs down Mile. Percy combs his hair in BG (Perform for Hi Speed)

Lens on Deck. Track back to reveal mouse (which may be difficult)
Shoot with snorkel or below deck level.
Var FPS on mouse

Try to get all in-camera, no VFX, no MoCo. Eliminate track?
Plan B: Motion control Pan/Tilt/Focus. Moving 2-element composite
Plan C: Eliminate camera move and focus change, shoot as locked off 2-element composite.

1) Actors, no mouse
2) Mouse, no actors
3) Clean Plate