I think the error is related to to long field names. The length of the names is 32 characters, and when you exceed this limit, the field should have gotten an unique ID, but for some reason this unique ID is put as the 33 character and therefore it fails. In my tests however I cannot recreate this error so it might be related to your SP environment.
The fix is to recreate the field names using only valid English letters and underscore and no spaces. In your example: “# of seats” should have been written like “numberOfSeats” or “no_of_seats”. When you have crated the field, go back and change the name to “# of seats” and you have a nice FieldInternalName and your preferred display name.