Kalshi says its vetting process blocked Gannon Van Dyke from opening an account. Bloomberg/Getty Images Prosecutors say Gannon Van Dyke used military secrets to make trades on Polymarket. Kalshi says he tried to open an account on its platform but was blocked. Van Dyke, a master sergeant at Fort Bragg, was indicted on multiple felonies. The Army Special Forces soldier indicted on charges that he used military secrets to win over $400,000 in Polymarket trades was blocked from opening an account on rival prediction market platform, Kalshi. Elisabeth Diana, head of communications for Kalshi, told Business Insider that Gannon Van Dyke did not make it past the verification and know-your-customer process but declined to provide more details. Reuters, citing an unnamed source, had earlier reported that Van Dyke tried but failed to gain access to Kalshi.…