Seravalli reported this news just moments ago, noting that the Oilers plan on signing Dermott to a professional tryout after he joins the team in an unofficial capacity for the captain's skate. This is likely just a precaution as the team wants to make sure he is in shape, but there is really no risk anyways with a PTO as they can release him before the season starts if it comes to that.
Dermott got into 50 games with the Arizona Coyotes last season, largely playing a bottom-pair role. He had 2 goals and 7 points and was a -14. In his career, he is up to 329 regular-season appearances, and has 16 goals and 62 points. He spent most of his time in the league with the Toronto Maple Leafs where he played in 251 games between 2017 and 2022. Statistically, those were the best years of his career as 12 of his goals and 40 of his points came in that stretch. He was also a +28 with the Leafs.