Supplements are like substrates everyone has their favourite brands, the thing is there is no regulating on these so companies can actually say whatever they want on a package and there is no independent body to check or regulate these products. I use repashy brand for everything but thats my preference.
Dust your feeders once or twice a week with calcium and definitely gutload your feeders, food quality is important with nephrurus and big species like amyae will benefit from the occasional pinky mouse especially coming into breeding season and during egg development.
Good luck, they are an awesome looking and easy to care for reptile.