Divorce Enquiry: proofs validity and child custody

My friend is in Texas, US now. She has been married for 5 years. She has a baby girl of age 2.5 years. She has recently found that her husband has an affair with his office colleague. The girl whose has affair with her husband is married and has 2 kids. My friend met her husband to discuss the situation. My friend has gathered some evidences about the affair of her husband. The girl with whom her husband has affair with has her location shared with her husband. So he can keep track of where she goes. So he had tracked his wife\\\'s location and found her quite many times at my friend\\\'s home in her absence. Actually my friend was in India last year for diwali and it was this time that, that girl was tracked to be at her home with her husband. She has a screenshot of the location and date on which the girl was at her home. Other thing is my friend has a recorded audio of her husband accepting his feelings for that girl. That girls husband has caught them red handed in their car 2 times. So he can also support my friend. Besides this my friend has some questions asked by her husband on some forum about the divorcing, child custody etc. But there is no name of him on that forum. She found that on his web browser history. So will this be enough to prove that her husband has affair with that girl? And also will she have her child's custody after divorce?