I am being told by installers that the dishwasher I bought is too big. Do you have one that fits into a a space 23 1/2 X 33 1/2 can you help

You probably need to find new installers able to measure these things more accurately if the consensus is that's what off here. Note though the question you asked was to the community and doesn't necessarily reach the Lowe's store itself nor it's employees (which I assume are also the installers whom I would hope have a line back to the store, but who knows)

The measurements are not good because they are going by the side trim should be 24 inches wide . Check again?

Your opening is to small. It should be 24 wide . And the height should be ok but sometimes takes a little work to jam that thing in the hole