Looks like he towed to 5700' and landed at 3200', so he only lost 2500'.

Correct.

The flight was well within the 1000m FAI allowance, which was planned
around. What I didn't plan on was overflying the conditions in the
panhandle. With the nice tailwind, I was on track to make or exceed
1000 km total but ran into stagnant air in an area which would
normally have yielded good groundspeeds and a late landing.

-Gary