Nah, he's not a poor manager for not getting proven quality - that was never suggested. I think some of his "lower league" signings will still come good.
He just has to do the best with what he has - and I don't see that happening. His tactics, formations, line-ups and substitutions have not helped. What I have seen too often is a side so disorganised, discouraged and lost for ideas that some of their performances wouldn't be acceptable at League 1 level.