Can someone who has experienced this problem please please guide me on how to fix it. 

2008 Prius Touring 175k with miles. The prior owner broke the trunk handle piece off and epoxied it back on. 

I have since broken it too, but the problem is, I have effectively broken the interior side facing the car where only 1 of the 4 screws can be used for mounting.

Even if I buy one of those metal support brackets, there is actually nothing  secure to mount the bracket to the actual liftgate because the mounting shrouds have torn off.

The other problem is that the 3 small screws to remove the black square button are all stripped. This also means the liftgate handle cannot be removed from the vehicle since that button is connected with wires that are coming from inside the car. Only the physical switch for the trunk handle has a removable connector.

I don't know what to do. I have been driving the car with the liftgate handle hanging off because it is only secured with 1 screw. I tried buying one of those replacement liftgates that come with a metal support bracket. I cannot use the bracket on the original part, and I cannot remove the original part either to replace it with the new since the wires are stuck on there.

  
I wish to preserve as much normal function of the car as possible, can anyone provide me with guidance? 

Complicated trunk handle replacement help