Help with new cypress deck

Folks,
I would greatly appreciate someone's help.
I built a fairly expensive cypress deck about 8 months ago and the builder's stain guy did a horrible job with the deck stain.
First shot at it turned out orange. The second shot was a natural honey color and immediately started mildewing.
They then went in a 3rd time with a semi transparent stain, and it too is apparently showing black streaks all over the deck, which I'm assuming is mildew. What should I do. This was a beautiful deck when first stained, but now looks years older than the actual 8 months that it is.
They used Sherwin Williams product, which I now question that decision.
This is a platform deck (low to the ground), so obviously, the wood is not stained underneath the deck boards. I took a look at the underneath, in the small area I could get to, and it does have black streaks on under side. At this point, I am pretty desperate and really don't know what to do. I have read just about all I can and am getting conflicting advice.
Thought this looked like a great forum to turn to and hoping to land some advice that will work. Does mildew creep in from underside of decks that aren't stained underneath. I've got to think most platform, low to the ground decks are not stained underneath.
Should I paint, solid stain, or what, at this point. I love the look of the cypress grains, and hate to have to give up on seeing that with a solid, due to the extra cost I invested in cypress, but at this point, I just want my deck to look good, it being so new. It has been so dissapointing. It's on a new house, as well.
first pic is of wood when new
2nd is condition after the light stain
3rd is condition after semi transparent--the black marks are multiplying rapidly.

thank you in advance for any help you can offer.