I have no horse in this race (cat in this box?) as far as multiverses and polycosmoi go. I will limit myself to clearing up popular confusions about Peirce’s concept of abductive inference. Analytic philosophy swayed many people into thinking that science could be reduced to purely deductive reasoning, eliminating induction and ignoring abduction, but Peirce was a practicing scientist who worked outside that warp. In his model of the inquiry process abduction is at root logically prior to any discussion of probabilities, however true it may be that all three modes of inference work in tandem to advance any moderately complex investigation. There’s more information on the history and function of abductive inference in the following article.
See especially the following sections.