I'd just like to start by saying, posting a screenshot of your resource packs doesn't exactly prove anything, because anyone could have just deleted the pack before taking the screenshot so...
Anyways.
You joined our server less than 1 hour ago. Within 3 minutes, you found diamonds, by tunneling straight down from the surface directly onto them:
Then you built back up with cobblestone, went over and tunneled straight down into a cave, and headed straight for the wall:
Straight to the next patch of diamonds:
Then over a bit more and down, straight to the next patch of diamonds:
From there not even the lava stopped you from getting straight to the next patch of diamonds:
This is some of the most obvious x-raying i've ever personally watched unfold. So no, I don't believe it was luck.
Appeal denied.