Max, I think there is a way to do this by using custom action. Instead of having the exit action on the taparea click/tap event, we can set it on the swipeable gallery frame tap event and the url can be set based on the currentIndex of the gallery.
Right click on the swipeable gallery and select Add event...
Select Swipeable gallery > Frame tap for event.
Select Custom > Add custom action for action.
Give the function a name, then copy and paste the following in the custom action:
var gallery = document.getElementById("gwd-swipegallery_1");
if (gallery.currentIndex == 1) {
} else {
}
where the gwd-swipegallery_1 is the id of the swipeable gallery, image_1 is the metric name, and the last 2 parameters are collapse on exit and pause media on exit.
You can also use the switch statement if you like for your 3 images.
I also attach the sample file.
Hope it helps.