During one of the loading screen a hint came up saying " 1 vs + 1 vs = ??? " This leads me to belive that there is some sort of vs combo that you can make, I've been testing things out with no luck. Also, if you ever see a large box with a blue outline, have your entire team shoot T-eng at it, once it opens there's a vs with a Nuke launcher (no joke) if you havent seen it yet, you must.

Didn't you read the post? In some maps, (maybe only layout type 4 only) there are giant boxes with blue outlines, you open them with extreme amounts of T-eng, the vs inside has a super weapon on it. I've seen two different ones. One had the nuke, and the other had a Jericho missile launcher thingy from the begging of the first Iron  Man.

I did find out the VS combo but I'm not sure if I should share it but I will,

(I dont know the real names) The nevec tank transformer + the nevec base VS, the one that cloaks.

all you do is get close and use both thumb sticks at the same time and then press be to merge, you get an achievement for it too.