I don't think Verbeek is in any hurry to trade Gibson at this point, but Gibson to Carolina makes the most sense if it does happen because they have players and contracts that would allow the Ducks to continue to compete and not just go into tank mode.
If Verbeek wants zero net retention, how about something like this?
Gibson at max retention (at 3.2 M, 6.4 million retained over 2 years) for Kotkaniemi (at 3.22 M, 6.4 million retained over 4 years). This would help Carolina with cap space in their window in the next 2 years and give them goalie insurance and Gibby gets to play for a contender and pay less taxes. Ducks would get a big center who can win faceoffs and has some untapped potential.
Maybe also include a swap of Fabbri at max retention, so 2 M for Kotchekov who's contract matches exactly at 2 million. Hurricanes get a forechecking depth scorer and Ducks get a decent backup goalie with some upside for the next 2 years.
I do think the Ducks would want some form of sweetener. Maybe a prospect swap of Dionicio for Badinka?