It was hoped that Hughes would be boosted by the American's return ahead of Saturday's Emirates FA Cup Fourth Round tie with Crystal Palace, following the recent injuries picked up by Ryan Shawcross and Charlie Adam.
The versatile Cameron would have been an option in both defence and midfield but will remain on the sidelines since his half-time withdrawal against Liverpool in the first leg of the Capital One Cup Semi-Final.
"He's not progressing as quickly as we would like and Geoff would like himself to be perfectly honest", Hughes told Stoke City Player.
"He's a little bit impatient about it at the moment but it's one of those injuries where we felt it could either be resolved quickly or drag on a little bit.
"We'll get to the bottom of it though, we've got an idea about what's going on and now it's just which way we go with it really.
"He's a little bit frustrated at the moment but he'll be okay."
Whilst the news further restricts Hughes options at Selhurst Park a number of changes to the line-up are still expected to be made.
Jakob Haugaard is poised to get the nod between the sticks after his Third Round appearance at Doncaster Rovers whilst the likes of Marco van Ginkel, Joselu and Phil Bardsley could be others who return to the fold.
Mame Diouf is also expected to make the matchday squad having missed out entirely at Anfield on Tuesday.
"I just couldn't get everyone on the bench," Hughes pointed out.
"I had a few issues in the back four and with Marc Muniesa not having played much football I was conscious of the fact that I may have needed an extra defender on the bench.
"That's why I went with two defenders, usually I only go with one, and obviously because of that somebody had to miss out.
"Unfortunately that affected Mame on this occasion but he's in my thoughts for the weekend."
He added, "After extra-time and 120 minutes we have to be mindful of the fact that a few of the guys could be put at risk.
"Obviously we've got a good depth about the squad and we'll pick a team that I think will beat Palace."