Could Scotty still give orders in Relics?

[Maurice]

Based on real world armed forces with ranks and all that, could Scotty immediately give orders in Relics after presumedly being considered dead for almost eight decades?

Discussed above I'm sure, but succinctly: No.

1. He's retired.
2. He's not part of the Enterprise's chain of command.

 

[Oddish]

1. He's retired.

Not to mention presumed dead.