He still had hopes of pulling you in with them, but he was far from feeling sure of you.
He undoubtedly gave Smiling Lou the cue to make the thing appear an ordinary case of highjacking while he ditched his whole load so that there would be no evidence against him if he lost out and you turned nasty.
"I'm absolutely certain, Casey, that if you had not been along, Smiling Lou would not have touched that load.

They'd probably have stopped there for a talk, exchanged news and perhaps perfected future plans, and parted like two old cronies.

It's possible, of course, that Smiling Lou might have taken some whisky back with him--if he had needed it.

Otherwise, I think they split more cash than booze, as a rule." Casey sat up.

"Well, they coulda played me for a sucker easy enough," he admitted reluctantly.