Thanks Imma!
This wasn't my first rodeo. I have three married daughters, and I washed every dress. They all had varying degrees of dirt, but I have to say, this one took the wedding cake!
I do have to thank everyone who gave advice, as I used almost every product mentioned. I've never left a dress in the sun for four days, and I think it was the final magic ingredient. Your encouragement kept me going. And no, I'm not going to make this my side-hustle. It gave me anxiety!
Thanks again to all who helped!