Rear glass bottom shattered panel replacement, how-to?

My iPhone 5s fell out of my top pocket and the bottom back panel shattered.

I am able to peal the rest of the glass off.

My question is if I have to disassemble the iPhone or can I just stick on a new panel i.e. Is there any support that the panel gets from the inside or is it just glued on?

Also, I am not worried about the long run of it falling off, all I want is to give it into sprints buy back program so I just need it to last through that.

P.S. I am aware of this article Rear glass panels and camera lens replacement, parts and how-to?

But here I am not concerned about it not lasting.

Also there the saffire lens broke and I read that there is something that attaches to the lens, as for the bottom panel there is nothing.

Thanks for taking your time to read this.