When supplying a JWKs key to static client metadata it is silently ignored by the library as the line that gets hit by the conditional check does nothing. It should return the created JWK. Client Metadata derived JWKs are also similarly ignored by the same line.
https://github.com/facile-it/php-openid-client/blob/ba2b298140df6b70c2e1422447055b5623e78a56/src/Client/ClientBuilder.php#L89
When supplying a JWKs key to static client metadata it is silently ignored by the library as the line that gets hit by the conditional check does nothing. It should return the created JWK. Client Metadata derived JWKs are also similarly ignored by the same line.