They’ve updated it all very recently. DM now shows as 22% Germanic, I think that was only about 4% before.
A large part of her family tree is south east England - Essex, Sussex, Suffolk. But nothing German or even from the continent unless you go back to 1680, And there are enough DNA matches with the right cousins/ 2nd 3rd cousins to be pretty confident a few generations back. So I’m guessing this is from a strong Saxon/ Angle / Jute ancestry matching quite closely with modern day native Germans.
I only come out as 4% Germanic so even more odd (I know we don’t inherit evenly but her 22% to me 4% is quite a German loss!).