2017 Ellis Island Quarter Red Not Paint

huh?

It's picked up the red colour form being buried in soil. Metal detector finds often look like this.

On a missing cladding the color will be red in color. When you look at the edge of the clad quarters, the red will be a deep red like a cent.

Also note the strike will be weaker because of the missing height of the planchet.
Coins found outdoors tend to be more brown, than red when a cladding is missing:

Detector finds:

The color on coins found outdoors is a stain on the surface of the coin. On the highest devices it will wear off there first:

A color difference is often staining from an event that happened to a coin in circulation like cup holder coins. We see these often. They are just from acid drinks alter the surface of coins. All events that happen to a coin in circulation are not mint errors. They happened after they left the press. So they are not mint errors.