To prevent accidental whisper rolls, require the person rolling to whisper "need", "greed" or "xmog" to the raffler. The text of the whisper will determine the roll bucket.

Change the raffle announcement to:
[LootRaffle] WHISPER ME NEED GREED or XMOG if you want [Gravitational Condensate] (or roll using the LootRaffle addon) within the next 60 seconds.

Completed. If NEED GREED, XMOG or DISENCHANT are present, it registers the roll in the correct roll bucket.