[AC Question]

I had a Galaxy S3 Verizon running on 4.2 and I could unlocked it to use if abroad. Recently moved to Asia and on the first days the phone software upgraded to 4.4.2 and about a week after the phone stopped recognizing the non-Verizon SIM card and it's been "Searching for service" ever since.
I looked all over the place and today I finally rooted my phone to enable the hiddenmenu on the efs folder. So now I can use some codes BUT the ones I need (which are *#197328640# or *#27663368378#) and when I try *#0011# the Service Mode page is all black and when it shows something after pressing BACK several times it says "No service".
How can I solve this?!
I rooted my phone with towelroot and I got Super SU as my administrator app.
Thank you all so much!