Feel? Does he mean literally? They can't ask or answer in any way but tapping, so they don't.

Beneath Hallownest's endless dripping, they hear soft shifting noises. Then heavier breaths. Then sounds of effort, muffled. Is he trying to move it manually?

They let this happen a little longer in sheer disbelief before intentionally thwacking the face mechanism a couple times. Please stop doing that.