I did a frequency check to see where this antenna is tuned. It seems to be tuned
for 26.500-26.800 MHz. The SWR is a flat 1.2 across that band. It starts to
when I go below or above that band.

Because of the close proximity of the roof structure inside the attic
you are adding more capacitance to the antenna than what would
normally be there.

In order to bring the antenna back into resonance you'll need to
counteract the increased capacitance by decreasing the inductance.

This is done by shortening the antenna.

I don't believe you'll ever be able to get your match as low as you
could in free air. This is because you'll get more induced antenna
currents whenever the antenna is located inside a house.