Hey Aubrey,
I suspect you’re fine, and it sounds like you did everything right. If it looks as it should after re-selecting non-square pixel on the event when you check it on your timeline, you should be good.
I say this, also, because this is a classic issue that stations are used to seeing, and (unless there’s a complete moron in the play-to-air department) they’ll know the adjustment to make if it looks incorrect on their end. You can even include a note for them to make sure they use non-square PAR.
Can’t wait for SD to disappear altogether…
–KG