When this was presented to our county GOP it also was said that if passed, it meant that those counties that passed it could not be challenged regarding sanctuary for non citizens also. In other words if there is a sanctuary for non-citizens then there is a sanctuary for gun owners. Or something like that. (Unfortunately our county commissioners failed to pass it.)
ie...nullification
Gun sanctuary and immigrant sanctuary are completely different and the first (gun) cannot logically lead to the second (immigrant).
Gun sanctuary laws protect and enforce the Citizens right to posses guns from local and State attempts to limit that right.
Immigrant sanctuary laws violate Federal law and infringe on the Citizens right to lawful immigration policies.
IMHO these are two different issues and cannot be conflated.
Fine. Take 'em up on it. At some point, hopefully, the SC court will ban this Sanctuary crap but reinforce the 2nd Amendment. Until then, pull a Cloward-Piven on 'em and do the same with anti-abortion and any other crack-brained liberal law. Sactuary the Hell out of 'em.