I did something similar February 2022, Mexico->US->Thailand, I thought I could show up in Thailand with the Mexican lab results but the Airline was funny about it so I had to get a test done in the US. I was only there for 24 hours and the Mexican lab results were only 48 hour or less.
I am going through the marriage visa process currently. It's a freaking nightmare. I would only recommend a marriage visa if you will not be traveling for 4-6 months. However, if you have time patience and no plans of going anywhere, it maybe an option for you.
Do you know this for certain? I ask because I was recently married and plan to claim her as my spouse on my tax papers. It was my understanding I only had to get a certified copy of her passport at the US Embassy.