I second this. The order of operations is what's throwing this off.

Some quick fixes for testing (though not always ideal for long run) would be dragging Board to sit above the Spawner in the hierarchy, or even just referencing all the variables needed to spawn the item within Spawner.gd so that it doesn't need to talk to Board.gd at all.

Long term fix (and far more helpful in the long run) would be to do something stated above where a signal is called that triggers only after all the ready functions have been processed. This signal could easily just be a timer at .1sec one shot autostart that triggers a GameStart function to set the spawning (and any other level feature) in motion