The ground tab connected to GPS?

Hi,

My question is if the so called "ground tab" has anything to do with the GPS signal? I replaced the battery and back case and since then the ground tab is not connected to the house. Doesn't reach it. If I loosen the screws around it the vibration motor won't work, and also not sure it would reach the house anyway.

I experience low and slow GPS reception.

(There were issues with the connector #3 as well after I accidentally broke it, but it has been replaced)

Any suggestion?

Thanks