I think a number of years ago, there was limitation on how and where a gun could be carried. However, over recent years, the codes have become more lenient in favor of gun carriers. I believe that now licensed carriers can carry a gun any way or any place on the body they choose. With all of the code reading and publishing on the ODT, I think we would have seen that restriction. I believe that unless a mode of carry is specifically prohibited, then it is legal and I don't think ankle, etc. carry is prohibited.
I think it should be up to the captain to show you where it is prohibited in the code, rather than your trying to prove a negative.
The last sentance pretty much sums it up.