Question:
How to transfer GV-Eye v2.3 dewarp function to a different android phone?
As you said, "Pressing the $2.99 button anyways still prompts to repurchase"
Answer:
Just follow the steps shown in the instruction. Repurchase -> Enter the credit card number and so on. For new phones (Android, log-in with the same account), Google play will ask you to follow the same purchasing process again even though you've already paid the money. (previous phones) But it won't really charge you. It's just part of the process and this only happens on Google play. It won't happen on Apple Store. If the customer gets charged again, kindly ask him to check with Google and see what’s going on.
Reference:
Re: [ UVS - 201611046001 ] How to transfer GV-Eye v2.3 dewarp function to a different android phone