[Sweetsour]

Well, UNIT_AURA fires when a unit's auras have changed. So when this fires, it sends you the unit that caused the event to fire. So you'd want to try something like this:

textFrame:HookScript("OnEvent", function(self, event, ...) -- Use "HookScript" instead
 
 
    if (event == "UNIT_AURA") then -- need to check to only run this code when the event fired is "UNIT_AURA"
        local unit = select(1,...) -- UNIT_AURA returns one arg; being the unit
        local count = 0
     
        if (unit and unit ~= "player") then
            return
        end
 
 
        --  Check player buffs against the roll the bones buffs
        for buff in pairs(buffs) do
            if UnitBuff("player", buff) then
                count = count + 1
            end
        end
 
        --  Give warning if need to reroll the bones
        if UnitBuff("player", "True Bearing") or UnitBuff("player", "Shark Infested Waters") or count >= 2 then
            textFrame:message("")
        else
            textFrame:message("ROLL THE BONES!!")
        end
    end
 
 
 end)