BURLINGAME — Eleven years after doctors told his family they weren’t sure if he would survive an inoperable brain tumor, 16-year-old Bosman Botha maneuvers around a ping pong table like an old pro.

A wealthy Qatari businessman’s campaign to lead the sport’s global body is being investigated. One of his critics was detained and interrogated in Doha. By Hannah Beech In a near-empty venue in a near ...