That is not accurate, and the article somewhat inflates the significance of a request for admission. Responses to requests for admission do not need to be made under oath or under penalty of perjury. The consequence of denying a fact that the requesting party later proves true is that the responding party may be ordered to pay the "reasonable expenses incurred in making that proof" unless the "admission sought was of no substantial importance" or "there was other good cause for the failure to admit."
Requests for Admission are a pretty useless discovery tool. It’s not hard to draft non-admission answers. Judges rarely force defendants to give a straight up yes or no answer.