The paper in question:

Dark Matter and Gravity Waves from a Dark Big Bang
Katherine Freese, Martin Wolfgang Winkler

https://arxiv.org/abs/2302.11579

https://journals.aps.org/prd/abstract/10.1103/PhysRevD.107.083522

Article about it:
https://daily.jstor.org/new-paper-argues-that-the-universe-began-with-two-big-bangs/
"However, when the dark vacuum energy transitioned into dark matter particles, that change of energy would have shaken the structure of space and time, creating gravitational waves that would fill the Universe. Metaphorically at least, this would appear to be a “hum” in the structure of space.

Very precise experiments have already reported detecting a cosmic hum, but a bit of caution is warranted. There are several astronomical phenomena that can generate a similar hum. Thus, the recent detection is not a confirmation this new theory. That will take more data and far more sophisticated analysis. However, the fact that facilities exist that can detect the right kind of gravitational waves gives us hope that researchers will be able to confirm or disprove this idea within a few years."

More recent paper by NANOGrav:
https://www.sciencedirect.com/science/article/pii/S0370269323005373

Resolves YES, if papers with experimental confirmation of the hypothesis are published by the end of the year 2025 that (1) are peer-reviewed (2) reach the the typical 6σ level of confidence (or a similar measure) (3) are confirmed by independent experiments and (4) the consensus is that other hypotheses can confidently be ruled out.
Resolves NO otherwise.
In edge cases, I will work with the community to decide the most appropriate resolution.

I will not bet on this market.