A couple of things J,
When an IM or legislative bill is voted or signed into law the true meaning is not know until case law is established. (What ever a judge or jury decides)
It may be a recently enacted law and the intent of the sponsor's well documented in the media and a judge with an anti opinion will rule the actual law passed means something else.
The limited case law available does support the convention, by the creators of IM #403, that Nebraska is a Constitutional Carry State, in that neither the state nor its political subdivisions may exercise police power over a power they have not been given.
Further until IM #403 there had been no power granted by the people to regulate firearm and with IM #403 the people denied the state the power to regulate firearms.
Omaha never had, even under Home Rule Authority, to enact their open carry permit scheme.
Lincoln never had, even under home Rule Authority, to enact their handgun registration scheme.
That did not stop Brad Ashford from pushing the Pistol Purchase Permit two years later.
The arrogance against the will of the people is phenomenal and they will continue to violate their oath of office until voted out or slapped down by the state supreme court.
Sadly the solution to forcing those in service to We the People is money, having a person that has been cited for an offence and a judge that is mindful of his responsibilities to the people he/she serves.
The other alternative is to vote into office those who understand that they serve the will of the people and not the other way around.
So in answer to your question, yes, if it is pushed it will take money and ultimately be decided by the supreme court.