Herald Sport understands Billy Davies' side are confident of securing Fox on a deal until the end of the season from Southampton.
Forest had targeted Wallace, and a representative of the club made four bids, all below £1m, before pulling out of talks. Graham Wallace, the Rangers chief executive, is believed to have insisted only a bid higher than £1.4m would be accepted.
However, while Davies is keen on the Rangers defender, the Forest chairman, Fawaz Al-Hasawi, was unconvinced about submitting any higher offers for a player in the third tier of Scottish football.
Herald Sport understands that no other interest in Wallace has been lodged at Ibrox.