Hello,
If you can try this "Lua Script" condition (instead of "buff stack" condition)
Lua Script:
local nameSpell = GetSpellInfo(114015);
local name, rank, icon, count, debuffType, duration, expirationTime, unitCaster, isStealable, shouldConsolidate, spellId = UnitBuff("player", nameSpell);
ret = count;
Return value research: 5 (if you need 5 buffstack)
Return value var: ret