Yes, I interpret the KS website the same way. It appears you can legitimately file as a non-resident of KS and a resident of MO.
KS taxes non-residents only on KS-source income. Income is "sourced" based on where the work is actually performed. Therefore your earnings from physically working in MO would not be taxable by KS if you file in KS as a non-resident.
I think if you're questioned you can say you relied on the information from KS' own website.
**Answers are correct to the best of my ability but do not constitute tax or legal advice.
