Edwards joined the development group on Monday as he stepped up his comeback from a back injury that has kept him out since February.
Fellow Wales international Vokes has been sidelined all summer because of an ankle problem, but manager Mick McCarthy revealed both are working towards full recovery.
"Dave has got to play some games because he's hardly trained from coming back originally," McCarthy told the Express & Star.
"He's got to train fully every day and play games and he will be fine. He'll join the main group when he's fit."
Meanwhile, Adlene Guedioura has returned to Doha, Qatar to continue his treatment after ankle surgery.
McCarthy added: "Adlene has had his operation and he's in Qatar having the first bit of his rehabilitation and then he will be back here.
"I have spoken to him and had text messages from him and he's feeling really optimistic about himself. He's optimistic that he will be back by the six weeks stated at the time or sooner."
Source: Team Talk
Source: Team Talk