Honestly, the only two that have me worried are the Sidereals. Given how long they live and their tendency to cut and run when things get bad, there's a very good chance that we're looking at a pair of 1000+ experience individuals to put it into game terms. Well, maybe one, Mr. Secrets (or...
Given that my original worry was "oh snap open space + archers = bad" I'd say that this is certainly infinitely worse.
I like your plan, though, certainly something like I'd try to convince my companions to do!
There's one problem.
Both Solars and Secret don't have access to their...
I dunno, made sense to me: Misho, while fleeing, charges out into an open field. Correctly noting this as a Bad Thing when being pursued by archers/ranged combatants of any kind, he skids to a halt. Shortly after Marena and Secret barrel into him.
Is this a correct interpretation of events?
Practically speaking, there went their easy escape route. Also, bravo Secret! A two-mile crack through stone and earth? Stone and earth compacted by water? That's impressive for a Terrestrial Circle mishap.