merge single layer to panoramic layer, changes color

Hi!

i'm trying to delete the tripod from a 360 picture, without losing quality, and I found that if I create a new layer in panoramic mode (with the original 360 picture) the quality is far superior than using rectangular to polar coordinate to fix it. but I get another problem.. I cannot merge the layer with the fix with the panorama layer because photoshop changes the colors.

have any one find a fix for that?

with the tripod

with the fix

with the blend (merge down, Ctrl + E) other kind of merge kills the panorama layer, and convert it in layer, loosing the rest of the picture, and I'm not using any blending mode 

please help!