Thanks for bringing this up. I'll explain why it's perfectly fine as is
It shouldn't be NC'd because both 00:27:853 (10,11) - (like 00:30:442 (5,6) - and 00:33:032 (5,6) - ) lead into the next measure and I try to do measure based NCs in this map (though it's somewhat hard sometimes because of the 5/4)
As an example where you said: the "Bo-ku" part is said before the next measure, and you can tell it's a strong new measure when the "hi" in "hitori" comes up with the Piano and the whistle hitsound supporting it.
So some people do actually new combo on lead in instruments or vocals (pkhg and Yohanes both did this on the map, but Doyak and I didn't), but I usually do not unless there's a very good reason. Hope this helps