2005 Pontiac Grand Prix radiator problem

I just bought my car and my husband said my antifreeze had transmission fluid in it. So I bought a new radiator and had it put in but the guy used green antifreeze instead of red he said it doesn't matter what color but my dad is saying it will gel up if its mixed and mess a lot of stuff up is this true what should I do. I noticed that the temperature gage isnt rising much and my heat doesnt get very warm still and the water in it is a rusty orange again