With a release date two weeks out, you are actually in a stronger position to get a special visit approved than you might expect.
Special visits are entirely at the warden's discretion, but wardens are human beings who understand that a family coming to see someone who is about to come home after 15 years and 8 months is not a frivolous request. The proximity to release date works in your favor because it gives the warden an easy rationale to approve it. The visit is not enabling ongoing incarceration or creating a complicated situation. It is a family saying goodbye to this chapter and hello to what comes next.
The distance factor is significant. If the visitor is traveling more than 150 miles to get to the facility, special visit approvals are granted with much higher frequency. It is one of the most consistently cited reasons that wardens use to justify the exception, and facilities are generally aware that asking someone to make a long trip only to be turned away on a regular visiting day schedule is not a good look.
To make the request, the visitor should contact the warden's office directly, not the general facility line. Ask to speak with the warden's secretary specifically and explain the situation clearly. The release date two weeks out, the distance being traveled, the length of the sentence, all of that is relevant context that makes the case. Put it in writing if possible so there is a record of the request and a document the secretary can hand to the warden for review.
Be humble, be specific, and be ready to provide documentation of the travel distance if asked. Two weeks from the end of a federal sentence is a compelling story. Tell it plainly.