Do you have a Jig? It's a small device you can plug into your phone and it puts it in download mode, then you can reload the correct rom. Do a search in the SGS2 threads if you don't know what I'm talking about.
S5 SM-G900T, Omega Rom, Omega Kernel, Stock bootloader and Modem
S5 SM-G900A, ViSiX, TowelRoot, SafeStrap
S4 I337, Omega, MK2 Bootloader SafeStrap
S3 I9300, Omega Rom W/Stock Kernel and Modem
SG NOTE, CRASH ROM V10.1 Plus
SGS2, SicOpaT's KI3 ROM, Kernel: Ninphetamine, Modem: KL1
Captivate 1009, Rom: Serendipity VII V2, Kernel: Serendipity Kernel 4, Modem: Stock Serendipity VII