Are you asking how come a plural marker wasn't added to make the noun SuvwI' plural, or how come this line doesn't include the -pu' that is in the original line in Power Klingon?
For the former: plural suffixes are nearly always optional in Klingon. SuvwI' can be used where the speaker means warrior or warriors. You can add the suffix to explicitly refer to more than one warrior, but you don't have to.
For the latter: the original joke is Doq'a' SuvwI'pu'? ghobe', SuD. Are warriors red? No, they are green. Why the course creators changed the line I don't know.