Yes, that's an excellent suggestion -- thanks, GP. And I would actually say on that basis that it makes perfect sense that Michael and Vincent said nothing to each other about Neri staying behind. Micheal probably didn't even have to tell Neri to stay behind to collect the checks -- Neri would know without being told, just as he knew that Michael would want Fredo killed at some point after Michael said to Fredo in the boathouse that "you're nothing to me now."

It is possible, though, that there was some very brief, perhaps non-verbal communication 'off-camera' between Michael and Neri as Michael and Vincent were exiting.