Dak Prescott is dealing with two major issues this offseason. There’s his expiring contract. And a woman also alleges the Cowboys quarterback sexually assaulted her several years ago. Prescott made an appearance at the Texas Children’s Cancer Fund Gala in Dallas Friday night. He took questions from reporters who asked him about both issues. Prescott addressed the assault allegations, but the Cowboys quarterback didn’t offer details, “I know the truth,” told reporters. “I’m confident in what we filed. Very confident in what we filed. I know some things have changed in their sense in where they …