I already solved this and am posting it here for others to see, in-case someone else has this issue down the line.
TL;DR specifying that an argument in a function should be a typed array causes the function to not be called.
Godot Version
4.2.2
The info
The function I had was this one:
func set_associated_input_action(action: StringName, events: Array[InputEvent]):
To make the function actually run, I had to delete the type specification for events, like this:
func set_associated_input_action(action: StringName, events):
This allowed the code to run correctly.
What is bizarre to me about this issue is that it was only present when running the exported game on my Steam Deck; it did not occur when running in editor or exported on my desktop machine.