Other details suggest 1 & 2 are unlikely - they tend to make this manoeuvre when the predator is still some way off, and at least one species (Thomson's Gazelle

Other details suggest 1 & 2 are unlikely - they tend to make this manoeuvre when the predator is still some way off, and at least one species (Thomson's Gazelle) won't stot when a predator is within about 40 metres. It seems unlikely that the rest would outweigh the effort needed to jump 2 metres in the air (3), and I doubt a lion is worried about a kick from a gazelle (4). But yes, other explanations have been proposed. There's a list on Wikipedia if you look up Stotting.