How to remove/replace spoiler

The spoiler on my 2009 Touring edition wiggles up and down when the hatch is closed like it is loose. Is this normal or should it be rigidly affixed to the hatch (which is what I would expect)?
Thanks in advance for any advice.

 

After removing the spoiler I noticed that I have the same issue with the metal on the hatch body being bent/bowed outward (eg. not letting the spoiler sit flush to the body). Can I get your take on how you "pounded back down" the metal (without damaging it)?

 

here's a good youtube video of removing the trim that lets you get to the spoiler. It says '07 and '09 but my '10 was basically the same thing.

 

What year is this Prius? Are you sure the metal bends? Is this the only way to reinstall the spoiler correctly? I'm trying now, and the spoiler is not sitting flush with the taillights? Please help.

 

Both my plastic end rivet clips broke. I bought 2 new ones from the dealership. I drilled out the old ones. Now that I start new do I just use a pop rivet tool? How do you attach the new ones just push down on the spoiler? I only want to do this once and correctly.
please advise. thanks.

 

The video above is a 10-15 Prius not a gen2