I just went on a trip, and when I got there I couldn't pull out (swing out?) those two latch-things (that also have the key-hole on them).
And no, they weren't key-locked.
We *finally* got it open (two of us!) by looking at my other (identical) suitcase, peering in, and soon understood how the latching-mechanism worked (by sliding a hook (that grabbed the suitcase top-half): "locking" it (not really locking with key, but don't know a better word at 5am up-all-night) when shifting if one way, and un-hooking the other way.
(The pushing in and swinging out of those latches translates into the horizontal motion of the hooks.)
ANYway..., we finally got it open, by using all our strength by pushing the suitcase top-half one way (left or right, I forget), and the bottom half the other way, attempting to "slide the unfortunately-immovable hook" -- the HARD way!