First resize the image to fit screen to allow you to see what you’re doing.

1. Select the layer with the clipping mask

2. Unlink vector mask from layer image by clicking on the link icon

3. Select the vector mask by clicking in it

4. From the tool bar select the “Direct selection tool”

5. With the selection tool click directly on the vector path…the individual vertices become active

Hit Ctrl + T to put you in free transform mode then while holding the Alt key move the reference point to where you want it and continue your rotate transform as usual.