This summary is not the rule. The rule text controls.
If your case gets sent to an alternative dispute resolution program (like mediation), you can still gather evidence and information from the other side just like you would in a normal lawsuit. This means you can still request documents, ask questions, and use other discovery tools before and after the mediation or dispute resolution session happens.
If there's a disagreement about discovery (for example, if one side thinks the other isn't handing over information they're supposed to), the judge handles it the same way they would in any other case. Going through alternative dispute resolution doesn't change your rights to get information or how disputes about that information get resolved.
The timing works both ways too. You're not limited to only doing discovery before the mediation session. You can also continue gathering evidence afterward if the case isn't fully resolved through that process.