A Corrupted and Violated SLA, say Cone of Cold for 40pts would deal 10 Unholy, 10 Unholy / Vile, 10 Cold, and 10 Cold / Vile.
The cold immune victim would be immune to the latter half (both of which are still Cold dmg)... making it Vile does not make it less cold.
Vile is not a damage type of...