Gravitational red-shifting in the biggest star. What are the real colors?

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The biggest star in the universe (that we know of), UY Scuti is a
variable hypergiant with a radius around 1,700 times larger than the
radius of the sun.
To put that in perspective, the volume of almost 5 billion suns could
fit inside a sphere the size of UY Scuti.
The star lies near the center of the Milky Way, roughly 9,500
light-years away from Earth. Located within the constellation Scutum, UY
Scuti is a hypergiant star. Hypergiants — larger than supergiants and
giants — are rare stars that shine very brightly. They lose much of
their mass through fast-moving stellar winds.
https://www.space.com/41290-biggest-star.html
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Imagine the gravitational potential on the surface of such a star, 5E+09
times more massive than the Sun. And only 9,500 light-years away from
Earth, discovered in 1860 by Germans.
Whatever the visible colors at its surface are, according to Einstein
and his gravitational red-shifting crap, the entire visible spectrum
(Hubble telescope) should have an incredible distortion when pics are
taken.
The star would appear severely reddish in our "perception".
Questions with the data from above:
1) WHICH IS THE RED-SHIFT THAT WE, INDIRECTLY, PERCEIVE?
2) OBSERVED NEARBY, WOULD GREEN AND BLUE COLORS EXISTS?. BECAUSE, AS
SEEN FROM EARTH, IT'S ALL RED DUE TO RED-SHIFTING.
3) ANYONE DARE TO CALCULATE THE PERCEIVED FREQUENCY SPECTRUM SHIFT FROM
WHAT IS VISIBLE CLOSE TO IT, WITH RESPECT TO WHAT WE PERCEIVE HERE?