yes its possible but like poncho said its kinda pointless. this is exactly what the playstore version does. its a hardcode but it still reaches out to the json to pull certain data.
Agreed nothing is waterproof not even aes encrypting the redirect , you can still find encryption key quite easily if you know what you are doing, to find the dns on a panel I would say a small percent of say these forum numbers know how to do it , not water tight but allot better than a hardcode