@Missy
I don’t know to how to read a code from IOS since I have an Android phone but you can send your receipt to the CoG support email to unlock the game in the main CoG site. Once unlock, you could access the code by adding /scenes/startup.txt on the end of the game link address.
More info: How To See Other Games' Code (current info posted in OP and Post 146 on 6/18/19)
I wish I could help though. But I am currently busy with work.