Sorry, you're right.
Actually, the mandible movements in the OP's case, with reference to his/her actual displacement diagram is OPPOSITE (as in inconsistent) with what they are in other people's cases where a positive for the vertical means up and a negative for the vertical means down.
Not sure what happened here with the mandible other than having to refer to someone elses Gunson diagram with readings where a positive for the vertical showed something going up and a negative for the vertical was down.
I also cross referenced that with an Alfaro read out along with the diagrams of movements. Same thing for the mandible. A negative vertical showed something going down.
However, with reference to the OP's displacement diagrams the movements for the mandible suggest the opposite where negative for the vertical is up.
So, my bad for not asking the OP to show the displacement diagram in the first place. But somewhat baffling that read out for negative verticals DON'T mean down but mean up in the OP's case when referring to the displacement diagram.