Yes, you're right. The only excuse I can give is that there's an error in the model. The mark for the inch is the same in both hands, not mirrored. This got me wrong.
I can't reuse the fingers, they are tightly glued, so I have to rebuild the hand. I copied the single parts in a single sheet and I mirrored the wrong part.
Now back to the workbench.
Best, Nando