Newhouse probably goes down in the primary in 2024, and Valadao wins the primary and is slightly favored in the general.
Are you forgetting about jungle primaries? Newhouse finished first in the 2022 jungle with only a single Democrat in the race, so he should make it into the top two fairly easily.
Is Smiley expected to run? She ran as a fairly establishment GOP figure in the senate race and I'm not sure she'd actually go for the seat unless Newhouse retired, or that she'd clear the anti-Newhouse lane for herself if he does run.