Thanks so much for your feedback. I actually got an answer from someone at Vectorworks telling me that what is happening is a 'bug' that is being worked out. In the meantime, this is what he said is a quick fix:
"With the labels that are not cooperating, select them (try one by one at first...doing a bunch may make Vw crash...so save often as you do this). With the labels selected, in the bottom of the attribute palette, click on the down facing arrow...it will pull up a menu starting with use default attributes...choose this, and almost instantly, you will see the geometry of the labels show up again."
SO helpful considering I had a 15 page Bid Set due the next day!