ive smoked bud that had been iso washed like a week after i washed it. I just let it dry out on a plate and i rolled up a joint of it. I def go high but it was a mellow not as intense high, probably was getting high off all the other compounds that were left behind.To my knowledge, what you're seeing is the husks of the trichomes which are made of waxes which the iso doesn't dissolve. The essential oils of the plant are actually contained within the outer shell.
Doesn't mean there isn't any chance of getting anything because I've ran iso'd buds and got return back from it.
I could be entirely wrong though