My tank mines are currently sitting at 1065/1060 kills yet the Auraxium medal and the certs i get from it haven't triggered yet. Looking up info about it, it seems this was supposed to be fixed about 2 years ago. Yet it obviously isn't. I go the the Planetside players website, look up tank mines, and it says I only have 687 kills. Wonderful.
As said above, it's 1160 kills. Also, vehicle kills count toward medals, but arn't shown as kills on tracking websites. So, you've killed 687 people with tank mines, and 378 vehicles. This was actually changed a few years ago - originally only player deaths counted toward killcounts, which made getting medals on things like A2A pods a huge grind.
You're absolutely right and I am absolutely blind. Do please use this post as an opportunity to point and laugh at my inability to tell the difference between a 1 and a 0.
Funnily enough, I seem to have got the Auraxium medal on tank mines at 1060, not 1160. I was surprised, but there it is. Probably just another glitch.