Guys if its the charging IC then its not the motherboard. This board is also known as the daughter board .
This board houses the charging port, the headphone jack and also the network IC .
It costs 4k at samsung service centres. I got it replaced twice because of water damage issues.
This is...
What are the Samsung service center guys charging as you mentioned that it was huge?
Also did you ask them to try to replace the charging board (daughter board)? As that's mostly the reason for no network. Had happened in my S9+.