like you say, it either will work or it won't.
You might give a thought to why it failed in the first place--are you a big guy? Did installers pack mortar under the shower floor to prevent deflection?
Also, how do you know it is leaking at the connection between riser and shower floor? It could be the P-trap...
Were it I, I would pull down my kitchen light, remove the junction box (make sure the power's off) and get up there with a flashlight while the shower is running to actually see where the leak is.
If you need to make a bigger hole, you can always install a big 4-tube replacement box light in your kitchen to hide the enlarged hole.
This way you would know...