Are the files on the SD card are the same for both camera models?
Is it safe to boot Magic Lantern from any card in any camera (or at least on these two models)?
You should assume absolutely not. You can inspect the Magic Lantern source code yourself. But a strong hint is that the Magic Lantern binary download is specific to each camera model.
In the source code, there is a
platform/<camera model> subdirectory for each camera model. The
consts.h file in each of those subdirectories contains hardware-specific constants, firmware identifiers, memory addresses, flag values, etc.
Simply comparing the first 20 or so lines of
platform\700D.114\consts.h should be enough to convince you that the binaries are different, and that you shouldn't use the wrong Magic Lantern binary for each camera.