expected 2099. but maybe tegra chip

Sudden reboots and shutdown are usually due to third party apps of dubious sources. Take away these apps and you will not see such issues. There are many sources of such apps the worst is the blackmarket. Install these apps and only blame yourself don't blame the phone. Have seen too much of such cases on my friends units who likes to download from such sources

I'm a little confused, cause I have the following for my phone;
PDA: I9100XXKE2
CSC: I9100OXAKE2
Phone: I9100XXKE2
So does this mean I can't flash with anything related to XWKE?

if feedback from other members are to be believed, you dun have to worry coz:
#1. its almost impossible to brick the phone
#2. if something goes wrong, just go to Samsung and smile at them... be nice. they will reflash for you and tell you dun flash (your phone, not other flashing) too much...

correct? 

Be careful , very careful using root explorer to change your system files. Depending on the parameter you wish to change, One wrong alphabet can just freeze and your phone will not reboot successfully. Than you pray your phone can still go into download mode - if not , you need to get a jig to fix it or send in to service center.