What would cause my barely used green bearing to do this?

Insufficient end-play .
Shims are avail.
Some after-market axles come " trim to fit " .
As per post #18 .

There sure is a lot of hoop-jumpin' and 'obligatory but undocumented details' to install bearings that were never recommended, to solve a problem that never existed.

Spacer this, trim that, shim the other, remove the button, install the shim, yak yak yak. This version, that version, install this way or some other.

And that's better than spinning an adjuster once every fifty thousand miles, how? Jesus, what a cluster f**k.