I am not familiar with the Tavor shotgun, but offer the following to further confuse the issue.
- Damn near every MA Dealer has sold the Keltec KSG which IIRC holds 7 rds/tube with 2 tubes. To date, I am unaware that anyone has ever challenged this as an LCFD violation.
- I asked Glidden about shotgun tubes >5 rds in front of 200 chiefs and LOs at his seminar back some years ago and his answer was that EOPS had issued some opinion that a >5 rd tube on a tube-fed shotgun could never be an LCFD. I KNOW that this is contrary to the black and white words in the MA (and former Fed) AWB. When I teach, I advise my students that this opinion could be rescinded at any moment. They can decide for themselves their level of risk aversion to live by.
IANAL, but I think that the legal issue is the same between the Tavor shotgun and the Keltec KSG.