Many casinos have signs saying that the chips are their property. What next do they come collecting and want their chips back?

I'd say write to the casino and explain what they are displayed for and ask for permission. The worst that can happen is they say no.

I don't know why BRC up in the North woods of nearly nowhere in Wisconsin would be against some free publicity for their casino.

I'd still like to see a legal answer to who owns the artwork on a casino chip. The designer, the Mfg. or the casino?