Postgresql: Installing the extension as a non-superuser on Amazon AWS RDS

I would like to allow non-super users to install a specific Postgres extension. According to the documentation at this is possible if I have hired Super User to not correct in the extension .Control File.

In AWS RDS, however, this is not possible because I do not have access to the file system. Would there be a way to stop them? .Control Parameters via SQL query? Or have I reached the limit of applicability offered by RDS?