Keane said: "I spoke to Bardo last week and he said he was thinking things over. He said he would be speaking to a Premiership club first. I haven't heard from him since then, which always concerns me.
"I've made the effort and it's down to the player, you can't force him to do anything. It's up to him. When you're in competition with a team in the Premiership, it's going to be difficult.
"We've put a good package in front of him, in terms of him coming here and getting games, and it's up to him now.
"If he wants to come, fantastic; but the longer it goes on, the more you worry."