This is someone who is giving the cra the finger and her lower rates are not competitive to your areas industry norms. As much as we all would like to tell cra where to go sometimes (they took back my mat leave money years ago because my husband was self employed (and payed his taxes) and I was employed by another firm. They took the money saying I worked for my husbands business because I would do the banking for him!!!)
Anyway, because these tax evaders effect our economy and potentially your business, I would report.