The profile pictures posted seem to show a very slight difference between the Gateron PBT and the Cherry POM (I am not familiar with Cherry POM keycaps, whether Cherry profiles regardless of source are identical.. one would think but you never know). Just eyeballing my Vortex Cherry keycaps against the Gateron PBT profile image, the Gateron PBT seems to match the Vortex Cherry profile.. are they a profile match?
If you have any (dark) Vortex Cherry keycaps on hand, would be interested in seeing an image contrasting it to the dark gray Gateron PBT with the Vortex.