I tried to do the instances "Red-Pass" and "Retake Weathertop" from the Reflecting Pool in Ost Guruth and it only offers the Fellowship versions of the quest, but the quest requires the completion of the SOLO VERSIONS, so this quest is effectively unable to be completed for me.

Nevertheless, I did the Fellowship version of the instance anyway, but it did not advance the quest. I imagine the same would be true for other people who have already done those instances and attempted to use the Reflecting Pool.