Classified LTA platforms

[quellish]

But was it AARS? Here is the full quote:

It points out that daunting technical challenges exceed those encountered in the development of high-altitude UAVs, a similar program that began with significantly more technical maturity but took a decade and close to $2 billion to develop. The vehicle’s planform as it transits the atmosphere to its mission altitude, payload mass fraction at these altitudes, and gas management represent just a few of near space’s technical challenges.

AARS had lift gas?

They also mention Quartz separately and don't tie it to the unmentionable $2 billion program. Isnt Quartz synonymous with AARS?

The PDF in question: http://www.au.af.mil/au/awc/awcgate/maxwell/mp38.pdf

It was. He is talking about two separate things - the $2B HALE program and "near space vehicles". The point being made is that the technical challenges exceed those of HALE UAVs, and this HALE UAV program cost a decade and $2B - so a near space system would conceivably cost more to develop.
He does not seem to be stating that the $2B HALE UAV used gas management.