Thanks for the suggestion, sonnyyu. My objective is not to get the specific file off the linino side but to trigger a file transfer from the mcu and back through the mcu (I'm using my PC as a terminal at the moment, but plan to investigate piping it over I2C/SPI in the future).
When I get some more free time I'm going to try disabling the linino serial bridge for Console, as discussed here, and replicate my functionality with some python (first time for everything!)