That -2 patch looks really good.
It looks like you re-used somebody else's code, specifically this project:
This isn't a problem. I believe we should probably use their source file which includes the author and the license, which is MIT, and compatible with Solr's license. I wonder if we need to include a license and notice file in solr/licenses for this code.
Regarding patch attachments, normally they really should be just named after the issue, for every upload, which means they all get named
SOLR-7409.patch. If I am making an alternate proposal on an issue that somebody else is working, I will sometimes do a name like SOLR-7409-elyograg.patch to keep it separate from the more official work in progress. Jira will automatically grey out all but the newest version of each attachment that has the same name, but the older ones will remain available. This is in line with the open source ideal of keeping all discussion and development in the public view.