"Could you hook up with me after this whole thing? If the train actually physically lets us board I might be able to run an' grab ya the record book I been keepin'?"

He figures if nothing else it would give people some idea of the worlds they'd helped. Of people they'd lost. "...An' maybe make a copy of it."

Because he doesn't trust a firsthand account to go missing should the worst happen. Seems a lot less did. Death read it. Maybe she'd remember everything verbatim. But that's a hell of an ask.