I don't understand them myself (something about a contained event within an uncontained one, or vice versa), and I don't know if Frommer would add that level of complexity. It's idle speculation based on what the forms look like, nothing more.  
 :::::IMP.PL ko wouldn't work for Tsun tutet tspivang ko, where according to the translation it appears to be a tag question. What's the context for Makto-ko ?