What they said is true. I had the same problem. The hinge will be screwed/fused to the aluminium laptop lid. When the display hinge breaks, it is actually the screw thread/molding in the laptop lid that usually breaks, check if this is the case. This is your worst case scenario.
So, the only way to replace the aluminium part of the lid is by taking it from another laptop. There will be ebay listings (mostly in ebay.com) that sell scrap parts from broken/second hand laptops. That is your only option for a cheap DIY fix.
The other option is to go the official route. Hope your's isn't a 1080p display. Will set you back by quite a lot of money, as they only had 1080p models for a little while in 2014. And for some reason dell doesn't provide 1080p panels in midrange models in India.
I have Dell accidental damage protection till 2017. When I informed them that the right side hinge broke on regular usage, they said that the warranty will not cover it, seeing as how it is not accidental damage but normal wear. But after some haggling with the call center employee and her supervisor, finally they agreed to replace the whole thing free of cost.
This is not an isolated issues either, happens all the time with Dell laptops. That is why I always extend warranty for Dells, totally worth it. For me the replacement parts cost 18K, I bought the warranty for 7K.