I have translated the song "God You Reign" into Creole and was told that the word for "reign" was renye. Is this incorrect or can I use "renye" for the English word reign?

yes, renye v. is correct.  Sometimes it's also written as reye, if you were to google it.
The noun is reny (ren-y), as in His reign will last forever → Reny li va dire pou tout tan.

Haitian Creole ↔ English Reference, Look up Haitian Creole and English Words