speaker blown out on iPhone

You don't have a bottom left speaker no iPhone does. Your iPhone has 3 microphones. The "speaker" left to the lightning port is no speaker, it's a microphone. The speaker to the right is a speaker and the second one is located near the front facing camera and the third one is located on the back.

https://vkrepair.com/wp-content/uploads/2018/01/iphone-7-microphone-locations.png

That's not a speaker. It's a microphone.

Regards

Giulio