IPhone 4s no service after trying to change screen?

So, I tried to change the screen on my iPhone 4s by myself as it was cracked… Well, that turned out to be a bad idea. I ended up ripping one of the ribbons (I think it was the digitizer ribbon), so instead took it to a shop nearby to have them fix it again instead.

Well, they opened it up and then told me that they couldn't do it because something inside broke. They showed me the piece that was ripped pretty much off of the motherboard and basically told me that if they fixed the screen, I wouldn't be able to get service because that particular piece was broken and my phone would just be searching for service.

I'm guessing that piece they showed me is the antenna. Is there any way to fix this? Will I have to get a new motherboard or just a new antenna? Please help! I'm literally dying here using my old phone that's an epic piece of ****! Lol!

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