Would you mind explaining who exactly you are trying to persuade to allow themselves to be evacuated? The tiny population on Larssen II, which will be evacuated before the action even completes? The Vulcans on Soltitude, who will allow themselves to be evacuated when they deem it logical? The science/listening post personnel, who aren't even living there permanently and who the action by its wording doesn't apply to?
The Vulcans on Solitude. I don't buy the "who will allow themselves to be evacuated when they deem it logical" line. We all know that Vulcans are capable of just as many stupid, bone-headed decisions as any other race. If the fears they will never admit to aren't soothed, it will funnily enough turn out that it's "not logical" to be evacuated, because that's how Vulcans and their emotions interact.
And I do want to evacuate them. Per this post, I think it can be done in only 2 months if we concentrate our teams. You notice the fear-soothing will finish the turn before the evacuation begins.