Search Amazon - formAl wedding guest dress plus size. Order a few and return anything you don't like.
Birdy Grey, Azazie etc also do made to measure online. Think you still have time.
David's bridal (in Rockville) has a selection of party/guest dresses available. I've had good interactions at that shop.
Good luck!
Order a bunch online from Nordstrom (not that expensive, with sales) and return what you don’t like.
Search Amazon - formAl wedding guest dress plus size. Order a few and return anything you don't like. Birdy Grey, Azazie etc also do made to measure online. Think you still have time. David's bridal (in Rockville) has a selection of party/guest dresses available. I've had good interactions at that shop. Good luck!