Did you buy direct from Mephisto? Sometimes it's just the roll of the dice. I personally don't think any germ method is better than another, it's horses for courses, and what works for one don't always work for another. But if a seed ain't poppin, it ain't gonna no matter what method is used.
My last big no germ was a 5 pack of Med Gom 1.0. The seeds looked old, small, black, and only 1 popped out of 5. I nearly killed the only germer, out of pure spite and anger [emoji317]