I’m pretty positive at this point that Ooma Office is deliberately selling the phone numbers and details of their Office clients to spammers.
I proved my theory by registering about 10 new numbers, which I can ABSOLUTELY CONFIRM are not recycled or reused from a previous business or individual. Long story short, EVERY SINGLE ONE OF THEM had spam calls coming in ASKING FOR THE USERS I CREATED IN THE OFFICE PORTAL BY NAME.
At this point, nothing Ooma can say will convince me otherwise. I just blame myself for not switching carriers a year ago.