In "manual mode", the current layout selects the target table for you. There's a drop down list in the dialog for selecting a target table, but the layout's table is already selected but your only other available option is "new table".
For a scripted import. You are not limited to the current layout's table and go to layout does not select the target table. Instead, that drop down that in manual imports only allows you to choose between the current layout's table and "new table" now allows you to select any target table in your file.
Thanks Phil. That got me going in the right direction. When going step by step, I found that I had kept the Inventory table as the target in the "Specify import order" dialog in the Import Records script.
When I changed the target there to Scanned Count, it selected correctly during the running of the script as well as showing the "new table" choice as you described, rather than being grayed out as it was when I was running the script the first time. I wasn't looking deeply enough into the script steps. Appreciate your help!