Well, I wouldn't have had a 17 year pick the dress up without me to go over the dress with a fine tooth comb. I mean, look, your DD didn't even bother to try the dress on or really look at it, even,
I would've let the seamstress know that I was going to put a stop payment on the check if she didn't respond to my call and rectify the problem, when leaving her the message. I would've given her that last chance to do the right thing. The threat of a cancelled check probably would've gotten her to respond & fix it.
Really though, $65 is a STEAL for the type of work needed on that dress. Sounds like maybe it's time to spend a little more & have the peace of mind of dealing with someone more professional. It sounds like this lady is taking advantage of you & the personal relationship you have.
Have you tried stopping by her house with dress?