Personally, I dont ever think trying to attract hedgehogs to the garden can be a waste of time. I am not an expert but:-
I think Male hedgehogs hibernate earlier than females so maybe its hibernating, either in the house or maybe elsewhere.
I have my feeding bowls set up in a half size coldframe by son made for me, so easy to just lift the lid an replenish food and the entrance cut in the front wont accommodate cats.
I have had a female and two jolleys nesting I the garden, mum has now gone to hibernate in one house and the hoglets are still feeding each night and are now sleeping in separate houses, so I have all 3 occupied I think.
I have a camera which shows other hedgies coming into the garden overnight but the leave again after eating and I take it they go off to nest.
