Ok if we are going with the Group Leader (not Wing Commander lol) was the only one with white noses... then how do you explain the other planes in that second photo that fyvsix posted.
(Image removed from quote.)
The 357th had long got away from white noses. If it was formation identification it would have been on the tail.
The aircraft in this picture are as follows:
413518 B6-D Ed Hiro HORSE"S ITCH
413681 B6-F Don Bochkay WINGED ACE OF CLUBS
413522 B6-G William O'Brien BILLY'S squeak
41372 B6-V Robert Foy RELUCTANT REBEL
Here is a different shot of 3 of the same aircraft with the same washed out noses, but you can see some of the color bands on the prop hub on B6-F and some checkering on B6-G:

Here is 413522 B6-G William O'Brien BILLY'S squeak clearly showing a checkered nose.

Here is 41372 B6-V Robert Foy RELUCTANT REBEL showing faint checkering and propeller bands that are almost washed out.


Here are some picture of known checkered aircraft which are showing white due to being washed out.



Finally, here is a picture of horses itch stating the type of film being used as Panchromatic film in bright sunlight.

I hope this helps you see that the noses were not white. The 357th was a very proud unit and these colors were for identification as well as unit pride. It makes no sense for the CO to have a different color. You do not see that in the 8th air force's other groups either.
S!
Fyvsix