The text is grammatically correct, it’s just using journalistic shorthand.

The implication is that “They” (The F-16s) will be stationed on the territory of Ukraine. Not that Kiev is stationed in the territory of Ukraine. You’re supposed to read it as two distinct clauses, and since the F-16 is the primary noun, it’s implied that it is the subject of the following clause. The broadcaster just has limited words to convey that.

Kiev is a metonymy, and the headline is a clarification for previous ones, where it was questioned whether the F-16s would be stationed in a NATO country, which has obvious dangers.