Gregory missed the entire 2017 season after being suspended for at least one year for violating the NFL's Policy for Substances of Abuse. The 2015 second-round selection has played in just two games since his rookie season.
The 25-year-old became eligible to apply for reinstatement in November but has yet to go through the process.
Gregory slipped during the 2015 draft from a projected first-round selection due to off-field concerns. The one-year ban marked the third suspension during the defensive end's short NFL career. He previously served a four-game suspension to start the 2016 season for his first substance abuse violation and served an additional 10-game suspension for violating the policy a second time. He also failed the drug test at the NFL Scouting Combine.
In February, Cowboys executive vice president Stephen Jones told reporters Dallas wasn't counting on Gregory's return in 2018.
"We assume worst-case on any situations, whether it's the money or availability, especially if players are facing suspensions," Jones said, via ESPN. "Obviously last year when we knew [Ezekiel Elliott] faced a possible suspension we kept extra running backs, assuming worst case. So we have to move forward, assuming that Randy is not going to be here. If he is here, obviously it's a big deal. First and foremost for him if he could get himself in a situation where he feels like he could actually play football."
Gregory has just one career sack in 14 games, but, if reinstated, would provide Dallas with more pass-rushing options heading into the season.