#SIL, the maintainer of the ISO 639-3 prepare a list of changes that people can comment on with the changes of the previous period. This list contains changes like codes for new languages, changes to existing codes and last but not least codes that are retired.
When the language committee decides that a request for a new language is not admissible, applying for a code is the best way of getting a reversal of that decision. This has happened several times.
So this is your chance to peruse the crop of changes to the standard. When your language is in there, we will be happy to consider your request for a Wikipedia once these changes are finalised.