Cached Files causing 186 "issues"

Have a question about the Defender plugin.
This is first time I've used it. I'm getting 186 error messages - but they all seem to be stemming from this directory:
/wp-admin/css/colors/cache/meta/

sample name:
/wp-admin/css/colors/cache/meta/wp-cache-10ec3dc6d37a0b02312707a2ecfda04c.php

I cleared the cache in WP super cache so I'm not sure why those files are still there. What are you doing the situation? Is it okay to manually delete the files from the server?

Thanks in advance,
Michael