O'Sullivan is set to play his first game after enduring a ruptured pectoral he suffered against the Brisbane Broncos three months ago.
Bennett will also hand youngster Harrison Graham his NRL debut entering the team for the injured Jeremy Marshall-King (shoulder niggle). Outside back Brayden McGrady will also make his first-grade debut.
"We wouldn't play (O'Sullivan) if we didn't think he can perform but he's just got to be careful," Bennett said.
"He's three months behind everybody now so he's just got to make sure he's not trying to do too much out there and just do his job.
"Kodi has been one of our main players in the last couple of months, he adds lots to the team as well.
"Isaiya does as well so he can go to the bench and get an opportunity from there, and it is a bit of a rest, he's been up for a long time.
"He's done a really good job for us but it won't hurt him (over the) next month or two, just in and out and playing a bit off the bench."
Joining Graham for his club debut with the Dolphins is Josh Kerr. Kerr was granted an early release from the Dragons after signing with the Dolphins for the 2024 season.
"The big moment for Josh is the fact that he's a Redcliffe junior," Bennett said.
"That adds to what he's gonna bring here and coming here and it means a lot to him, his family all live here still.
"He's come over here, so I'm looking forward to seeing him play."