[There is no way to explain it properly. Whatever he says will cast him in a poor light, especially in Archie's eyes.

And yet...]

We would potentially risk the lives of everyone who might come with us for someone we have no more reason to trust than those who want him.

[It sounds like cowardice. Maybe it is. He isn't sure he could swear that it's not.

But it's also a way to keep his crew out of danger. Maybe, depending on what they have and what happens, a chance to present a second front.]