that's odd, on_entity_destroyed
only gets triggered after a player enters the capsule, at which point this mod will read the dropdown to see if emergency burn is selected or not, though not looking at it it might be because the dropdown wasn't touched at all, either way this crash is intentional when it cannot determine if it is an emergency launch or not (since failure to know it 100% certain could still result in 50% of the inventory being lost)
i am not in a space exploration run myself rn so i won't be able to test a fix for this in person, but for now i would recomend not deconstructing it if you have entered it and didn't interact with the target selector dropdown yet. π€