Yes, the Dehypon is ok to use as wetting agent in this mix.
As far as the crystalline citric acid, this is where I stop. I am not getting into the formulating of products. The DWV + some drops of a nonionic surfactant wetting agent is as far as I go. 5% DWV is not the same as 5% citric acid, the citric acid is a stronger acid so you use less. Exactly how much less, can be calculated and then you into weight measurement which then further complicates the process - all more than I am willing to do. You could pose the problem at some chemistry forums and see what they would recommend to equal the acidity of 5% DWV and then dilute as specified.