Except this sounds like an outdoor event, and 51% only applies to premises (inside or part of a building).
I agree that the 46.035 is poorly written. Based on the definition of premise (building or portion of a building), (b)(3) would prohibit you from carrying in a prison, but you're ok carrying in the outdoor prison yard.
I think a court would interpret "premise" to include an outdoor area that's fenced-off. Depending on the judge, it may require that the outdoor area only be accessible through a building (to include the outdoor dining area of a posted 51% establishment). Or it could be any outdoor area that's fenced off and posted.