I have iPhone 5S without PM8018

I buy iPhone 5S on ads....no IMEI or Modem firmware...not on iCloud. He restarts every 3min. Cant charge on power adapter but charge on PC. Fast recharging...tooo fast. I open front glass and saw than motherboard not have EMU shield and missing IC PM8018. My question: whether it is worth to change this IC or not? Thanks!

Here is pictures before:

In service they replace PM8018 ic and now iPhone 5S is working fine (now IMEI and modem firmware is visible)... but TouchID not working (Home button woking fine). And now strange things is happening: iPhone only charged on PC not on Apple charger...and too fast draining battery when leave on night (DND mode, no notification). And only charge battery when PowerOff iPhone (when is PowerOn iPhone restatrt every 3min).

I suspect on charge connector on logic board or components around...

This iPhone (before I buy) is water damaged...

Probably water damage on board but I cant see where...

What do I looked on logic board? Which component?

p.s. In service they replace my logic board in other iPhone 5S case ....

Here is 2 missing component near battery connector...