Well....there are so many varied opinions because we all live in different parts of the country (some of us in other countries) with different climates, different humidity, & lots of different incubators. What works for Joe in Washington may not work for Mary in Maine...even using the same equipment, because their climates are different...the place where they keep their incubator is different, etc.
I live here in Louisiana too...I hardly use water the first 18 days & then very little the last 3 days for hatching. The ambient humidity is so high that my problem is keeping humidity down....not up as most have trouble with.
The best advice I can give you is to learn YOUR incubator & how it works for you...keep records on everything at first & then keep doing what gave you the best hatches. Start with the basics & then tweak it to what works for you!
I can't help you with the turkeys, I hatch silkies & showgirls in a Dickey cabinet incubator. My temp is 99.8 to 100 & humidity is 35% to 40% the first 18 days using only a small cup for water....then I bump it up to 65% for hatching using a sandwich size plastic container for water.
99.5 is the target temp for forced air incubators (with fan) & 100.1 for still air (without fan). My humidity rates may work for you as we're in the same boat with humidity.
I'm sorry I could not be of any more help than this, but it really is a learning experience through trial & error.
Best of luck & we're always here to help if we can!