@sfstereo , found my multimeter. Forgot I had another toolbox. The faulty tweeter, as expected, shows an open load (infinite resistance).
@audphile1 , the retailer has been very responsive even late last night, and has said they will try to figure out how to get me a new tweeter (either through a spare that they have in the shop, or ordering through B&W). If through B&W, the lead time will be very long, I assume. I'm sure that the retailer must have missed doing a thorough check of the speakers when they acquired them to sell.
@jon_5912 , guessing your theory is correct regarding this tiny wire constantly flexing and eventually breaking. I’m wondering about purchasing a backup tweeter from B&W just in case - I plan to have these speakers for a very long time, as I feel I’ve managed to get to my "lifetime system". But you know how these things go. The replacement tweeter is very expensive though - they list it at over $800 USD (this is just for the tweeter itself, not for the full assembly which I wouldn’t need and is even more expensive). Wonder if I should pick up a spare crossover too!