Try all the different ways to change the wallpaper and see if you have the same issue in all methods.
1) Hold down on lock screen and then click on top left to change wallpaper.
2) Go into gallery, find a wallpaper and then set as wallpaper.
3) Settings-Wallpaper & Style.
Do all those methods still have no options on the bottom?
I say this because I had a similar issue with no option on the bottom but then by using a different method all options were available. Problem is I can't exactly remember which was which. Furthermore, for some weird reason, it's fully working....all the above methods now show me the options on the bottom. Might be worth to clear cache via Recovery mode.