Do they carry bottom plate dentures at the store locationñ,?

Only if they have a dentist there I've never heard of Walmart having a dentist at their location so you might have to call them and find out

There are no dental services available at this location.

The only thing they carry that comes close to a bottom denture is a top and bottom veneer set for $23.99. If you are talking about a repair kit for bottom dentures they do carry that product.