thats not ssj2 gohans hair. i think ive seen that style somewhere before, kinda looks like ssj1, because ssj1 hair is always plain, and ssj2 has way more details/lines. Anyway here some pictures of real gohan in ssj2. His hair is wide, long, and has a lot of lines.
but then after beating vegeta goku wouldn't need to go to namek, and he would never meet frieza and never become super sayan. and then gohan wouldn't become a ssj as well, then when cell appears the z fighters would be killed..
i just noticed installing esf 1.2.3 that its a beta version. it says full installation on half life 2 files, but the filename is esfb123.exe
and then during the istallation on the top bar it says earth special forces beta 1.2.3 setup