I made a new 'Twitch' profile with three mods:
Astral Sorcery 1.8.8,
Advanced X-Ray 1.4.2 and
Baubles 1.5.2.
all on Minecraft 1.12.2 and Forge 12.23.3.26.75, but not a single ore has generated. Nothing shows up on the X-ray, and no rays emanate from the ground holding the resonating wand at night. The temples and the floating crystals inside of them still generate just fine however.
This was in a completely default world gen, except for 'cheats allowed'.

Workaround: set 'IgnoreBiomes' to true in the worldgen rockcrystals configuration section.

With that enabled, they are spawning now.