[Choonstertwo]

UnitAura(unit, spellName) returns information for the first aura with the specified name, so it's unreliable when you need to distinguish between two auras with the same name. You'll need to iterate through the unit's auras using UnitAura(unit, index) until you find the one with the right spellID and then return the appropriate string for that aura.

oUF.Tags.Methods['SS'] = function(u)
    local i = 0
 
    local name, _, expirationTime, unitCaster, spellID = ""
 
    while name and i <= 40 do
        i = i + 1
        name, _, _, _, _, _, expirationTime, unitCaster, _, _, spellID = UnitBuff(u, i, "PLAYER|CANCELABLE") -- Only look at cancelable buffs cast by the player
 
        if spellID == 148039 then
            local spellTimer = (expirationTime-GetTime())
            if spellTimer > 0 then
                return "|cffFFAB00" .. numberize(spellTimer) .. "|r"
            end
        end
    end
end
oUF.Tags.Events['SS'] = "UNIT_AURA"