If you select the “slab plywood” door style, it will override the “solid wood slab” option, even if that is selected. Solid wood slabs are only available when a five-piece door style is chosen.
Long story short, about five years ago we launched barkermodern.com as a standalone website focused solely on slab-style doors. The goal was to eliminate confusion like this. However, once we got into the details, mixing real wood options with plywood and imported laminates that closely mimic real wood made the site difficult to keep clear and easy to understand.
At one point, we removed slab plywood from the Barker Cabinets website entirely, but due to strong customer demand, we brought it back since it continued to sell well. As a result, we are left with this somewhat awkward override behavior during ordering. It is not perfect, but it works. The only real fix would be launching a completely separate cabinet line or website just for real wood slab plywood doors, which is not something we plan to do 😉