step #19 on (how to remove logicboard) gold prong (PART NAME)

I bought a iPhone 4 that had water damage and in the tear down to clean everything with alcohol. I noticed that the little gold prong had what appeared to have rusted or eroded away. that the ifixit.com guides warns you not to damage in step #19 of the iPhone 4 GSM AT&T iphone guide. #

What is this part called?

how is the repair done?

is there a part number?

where can it be bought at?

please provide any and all detailed 411 you can.

I have enclosed a photo pointing to the part and drew a box around it to show it upclose.

thanks for the 411 to any one who replies.