Replace the anode in the Hot Water tank if it has one.
Otherwise run a "Sanitizing" procedure again..
Sulfur stink can come from organic matter and bacteria in the water source and if it sits long enough sulfur is generated through biological action..
Another source can be due to the local geology too. I lived on a farm where our deep well's water had a sulfur "aroma" to it. We just got used to it then but a good charcoal filter will help get rid of it.
On that note have you replaced your filter element in the water system?
"A wise man can change his mind. A fool never will."
"Sometimes you're the dog, sometimes you're the tree"
2018 Flagstaff Micro Lite 25BDS
2004 Nissan Titan