Essence: Remnants of Corruption cannot produce corrupted essences

It seems that using a Remnant of Corruption on an essence monster can no longer produce the corruption-only essences (Insanity, Horror, Delirium, Hysteria).

I have tested this on many monsters who had one of possible bases for this outcome (Scorn, Envy, Misery, Dread) with and without the Remnant upgrade Scarab, and have not once produced a corruption-only essence.

While this sample size may seems small, several reddit threads exist on the subject as well, and the current market availability of corrupted essences is insanely scarce, most likely stemming from other sources like Vaal Temples.

Related Reddit threads:
https://www.reddit.com/r/pathofexile/comments/1bssckv/using_remnant_of_corruption_does_not_transform/
https://www.reddit.com/r/pathofexile/comments/1btu9p5/essence_bugged_or/

Having the same issue, have not had a single outcome with an essence of corruption producing a corruption-only essence this league