Missing Copper Bulb in Trial Chambers

In the corridor end structure in the trial chambers (Corridor end 1 and Corridor end 2), one side of the room has a missing copper bulb, instead being replaced by a Chiseled Tuff Brick.

Seed: -1290695962
Coordinates: -1001, -23, 131

Observed Result:
The block is a chiseled tuff block.

Expected Result:
The block is a waxed copper bulb.