So yeah, the Head Doctor appearing all over the place was now confirmed to be a Stand attack, which means the head doctor might not even be real, but the Stand form itself.
Knowing the Head Doctor is a Stand, my guess is: the Stand makes you focus SO MUCH on the head doctor, as such, the trigger is focusing on the illusion if a old man walking around with a cane! Doing that trigger it's effects. You're basically chasing a ghost, he doesn't exist. Your goal should be to chase the User.