After discussing with @R4356th about his php and other programming experience, he told me he's actually written a MediaWiki extension, and has extensive php programming knowledge and experience. Additionally, he has knowledge of and experience working with and reviewing code for potential security vulnerabilities (including, but not limited to, SQL injections). So, after a brief conversation, I recommended he apply to volunteer as a security reviewer. As I understand it, @Southparkfan will likely review the request, recommend he review an existing pending extension in the queue, and provide some sort of analysis. After that, @Southparkfan, together with any other Site Reliability Engineering team members, will review the request and make a determination.
At any rate, at this point, I'm going to turn it over to @R4356th to discuss in more detail his relevant experience.