McCoy has years of working experience with Starfleet in assessing the viability of Strange New Worlds™ for habitability, in relocating peeps from planet to planet and safely resettling them, so he will be pretty keen to take point on that end.

Following their talk with Yerek on day three, McCoy will have taken the liberty of doing some intense analyses of both Hivawei physiology and the planet itself, working up a dataset of the necessary requirements they will need of any planet they're moved to. This'll go with anyone on the scout team, to streamline their efforts.

He also has the necessary tools to eliminate guesswork and determine safety, quality, etc wherever they go, but as he noted to Itachi, they're pretty specialized. If copies can be made of them, McCoy will give a crash course to the scout team! But he's gonna consider it his responsibility if anything goes awry with them so he's coming along.

He's also suggested they look at planets in the system first, as Viveca had mentioned.

Tl;dr:

1. Disseminate his (and other orbers') findings among Scout Team
2. Go forth and survey potential sites for resettlement
3. Confer with Yerek and any leadership
4. Evac the Hivawei who wish to go
5. Gtfo out of Dodge