Not likely to be covered.
Enough scratches along the edges of your device to show this is likely due to mechanical stress and not a latent product defect.
You may be able to order some parts to fix it yourself or find a local shop that can replace the keys or housing (depending on what has snapped off)
Double check which variation of the Touch Pro 2 Telus actually sold before ordering parts. Worldwide there were multiple phones marketed as a Touch Pro 2 and they are not all exactly the same. I believe the Telus version is part number T7379. Some parts may work on any version and others will not fit the CDMA version (especially true for a full housing). If the broken plastic is on the button only it should be a cheap repair. If there is plastic on the housing of the phone that is broken off then it will be more expensive to fix. Make sure you check on Kijiji, ebay, craigslist, etc for someone selling a used Telus TP2 that may be cheaper than fixing yours.
Unfortunately HTC phones are not known for their durability so you need to be gentle or what you may consider to be normal wear and tear will end up destroying your phone.