I would start by using your meter to measure the voltage of a 9V battery, just to be certain that the issue isn't using the meter itself.
The red wire going to A7 needs to be pushed in more. If all that exposed wire starts touching other terminals, you will make tons of problems.
I don't see anything obvious from your build photo that would prevent the power supply from developing high voltage. This issue is not the 12AU7. You could pull all the tubes out of the amp and there would still be measurable high voltage present while it's running. The fact that the LEDs don't glow but the tubes still do does suggest that there is an issue in your build. It's really, really, really important not to focus on the LEDs as the cause of your problems. Oftentimes there is something else that's not quite right which prevents the LEDs from illuminating, so I would suggest leaving them alone for now until you can get some reliable DC voltage measurements.
Lastly, I would go through and reflow every solder joint in the amp. It will take you 15-20 minutes, and you could add a little solder to each joint and a lot more heat. This is what I do for all the flat rate repair Cracks that I receive, and it fixes the vast majority of them.
