Onuora and Daws are both still training with the club as Groves works round the clock to either extend their loans or making permanent signings.
Groves does have the cash to sign Onuora until the end of the season, but Daws represents a more complicated issue. It is not sure if the board are prepared to make extra money for the Rotherham man, despite Groves' clear wishes to keep him.
"We're in negotiations with both parties and looking at every possibility, but it's too early to say whether they'll be in the side for Barnsley," Groves told the Grimsby Telegraph.
"The pair of them have grown in their performances since they've been here, and the team has grown with them."