The 28-year-old striker moved on loan to Norwich City in the January transfer window, but his current deal is due to expire on May 6 and there is no future agreement in place.
Vermes told the MLS club's official website: "We are looking into it, but I haven't heard anything yet. We have already negotiated everything. Other than Kei saying he doesn't want to do it, it would pretty much go through.
"They are not really sure where they sit right now and where they are going to go. If they would be a little more secure in their position in the league, I think it would be easier for them to make a deal one way or the other. Right now, I think that is why we're not hearing anything."
Norwich currently sit 14th in the Premier League table.