I don't know how you would fix it without taking the roof off, but taking the roof off is very easy, it takes about 3 minutes -- mostly due to fumbling around.
The roof has 6 torx screws, three on each side, holding it on. The holes that the screws go through are bigger than the screws, on reassemlby you leave the screws slightly loose so you can move the roof panel around to make it flush to the surrounding roof, then you tighten the screws the rest of the way. Slightly loose means tight enough to hold the panel in place, but loose enough that you can move it up and down.
When the roof glass is out, there are two more small screws on the shade itself. These screws are on the driverside frame rail for the shade. You can elect to repair or replace once you can actually see what has gone horribly wrong...
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