Aquarium fish should never be released into the wild as I’m sure you are aware regardless of if they are native to the area or not.
As for keeping musky I have no expierience but I’ve kept northern pike. I grew out a few in a 120 wide up to around 12”. Did this with 5 different fingerlings (never had more than one at a time). Took around 1 year for each to hit 12”. From there they were released into my million gallon pond. The pond was full of largemouth bass, bluegill, perch. All would reproduce yearly. After the pike were introduced all other fish populations declined. I found 3 of the pike dead after one cold winter when I went diving in the spring.