Can I bake this in a single 8 inch tin and cut into layers later instead? How long would I need to bake it for and would the temp need to be lowered t

Haven't done the adaptation for this recipe but yes for others.
Even though the original layers are thin, I would fear that four pans' worth of batter would overflow one pan same size.
Instead I would bake the whole recipe in two layer cake pans (8 or 9" round), same temp, about half hour, and cut them in half horizontally to get the 4 layers.
Or all the recipe in a large pan (12 " bundt, 10 or 12" tube or 9x13" rectangle) about 45 min at 350. Then slice horizontal layers from the tube pans or 4 rectangular pieces from the lasagna pan and add icing.
In all, check for doneness before the estimated end, use regular tests...toothpick, feel at center of cake when it's done.