W_Spigot makes no sense. Unfortunately, that is just how it is.
In total, W_Spigot.mdl is referenced in 7 different unique maps in the wc map pack:
Kleiner, subt, d1_garage, vert_01, d4_palace_01, testroom_stairs, and cremator. Of these 7 maps, the model is consistent between these maps:
1. d4_palace_01 and testroom_stairs


2. d1_garage, vert_01, and cremator



On the remaining maps, its rotation is a wildcard.


Perhaps the issue comes from the usage of the qc command "$upaxis." Maybe using $upaxis would turn it in a way that is consistent between all levels. However, in my work, I have not been able to find a solution that works in every situation. Therefor, I am turning to the community with resources to help try and find a solution.
Provided in this thread is a map file that contains every unique area that the model is used in, rotated around the model itself so its rotation is "0 0 0." If no good solution can be found, MP5 will be releasing with the model seen in the images, which was my best solution to the leftover texture and the model name. God's speed, and best of luck.