Considering that all three of those agents committed very obvious perjury in the last episode despite Gibbs telling them to tell the truth, I’m not sure if Vance is making the best call, but they were also worried about Gibbs and not the most objective when they decided to lie for him.
A link to a previous murder case will provide a connection to their work, and whatever they do will evidently be without the oversight of Gibbs.
That presumably won’t be the case for the case of the week.
Vance isn’t sending McGee and Co. right out onto another one of their regular missions, but rather COVID compliance duty at a foreign affairs summit.