where they hid / were hiding [past continuous] – WordReference Forums

The sentence is set in the present, so the question of a particular time in the past does not arise. To me, the past continuous is an odd tense to use and the present continuous would seem to be more appropriate, but I suppose the writer thought that as soon as they jumped out their hiding was in the past. Similarly, I would expect the present perfect instead of the simple past for your other …