It may be just a rumour, but all three are a bit different as player types than the current preferred players in their positions. As results have picked up of late Adkins may have decided to go with the current plan, and these three may not quite fit in.
In central midfield we've prioritised work rate and solidity at the expense of creativity. When I've seen Wallace I've thought he's potentially brilliant on the ball, and can also get stuck in, but he has weaknesses defensively, maybe related to his fitness issues.
Scougall is better in a three man central midfield, and also lacks the physicality that's important to the way we play at the moment.
Adkins has tried different types of wide men and he could be happy with Coutts and Woolford as they bring some solidity. We've been struggling defensively with too attacking players (JCR, Adams) out wide.
It wouldn't surprise me if these three were let go, with Adkins looking to find more similar types (maybe better) to the current first choices.