Yes: Doppler-Shifting of light is the ONLY method I am aware of (for now) that tells us the universe is expanding!

But keep in mind, that light and radio (photons) is the only way we even know something exists out there in the first place!

So, ya, I think it's safe to say 99.999 percent of scientists believe that "light" is a real thing!

So one can not really ignore the evidence that light brings to them.

If anyone is going to begin doubting the Doppler-Shifting of light as adequate proof...

Then that person may as well be asking,

"Is light and radio the only way we know the Andromeda galaxy exists?"

Or even:

"Is light the only way I know there is another car in front of me, while driving!?"

And what does this light show us about the far side of the universe?

Overwhelmingly, light says that everything is moving away from us at ever faster speeds.

(In our local region of the universe, there are some things moving closer to us... but further out, everything is being spread outward at insanely fast speeds.)

FINALLY...

Aside from light, there are two other methods of knowing that there is "something out there" that comes to mind, including:

1) Gravity

2) Neutrinos.

But we've only just begun building gravity and neutrino detectors.

Perhaps in the future they too will have sufficient resolution to give us more detailed information about very distance objects on the other side of the universe.

So I'm not sure that neutrino or gravity detectors today are advanced enough to confirm the expansion of the universe? (Maybe someone else here knows.)