That's a bitch :/ I remember when I first got them, I came to this thread and read that since they were sanforized hot soaking was not necessary. Actually read here that hot soaking would make the denim more prone to crotch blowouts and things of the sort , and it would result in cheaper looking fades.
If anything soaking should deter blowouts. Cheap looking fades, what does that even mean? Initial soaks will do nothing but get rid of any shrinkage left and remove some starch. I'm sorry you were given wrong information, that's a bummer. I wouldn't be too worried or expect a lot of stretch after you wash your denim. I highly doubt they will be unwearable after your wash, granted they aren't as tight as leggings at the moment.