There is a flock of ducks swimming in the lake a bit opposite the doctor.
You better wait till he activates his route and starts to speak with those ducks.
It might be that before he starts that ducks are not there and they appear when he does that.
When you see swimming ducks just throw any object in their direction, they should be scared and fly away.
That’s the trigger that makes a doctor go to Janus’.
I don’t know why you can’t see the ducks, but in case they are still there but not visible, here’s the reference where you need to throw an object
