if the mycelium gets contaminated and someone grew the shrooms anyway would the shrooms look the same? and if someone injested contamintaed shrooms what would happen
The mycelium would be probably make the shrooms not be able to grow, you'd be able to tell by a green or brown color, and they would become aborts. If you ingested contaminated I don't really know, I think you'd be smart enough NOT to eat a green shroom...
Contaminated mushrooms can kill you. End of story. If you find your mycelium is growing mold, presenting discoloration, or in any way behaving differently than it should, destroy it. You can ask here first to make sure what's going on, but any obvious moldy growth means you need to abort it. Only very experienced mushroom experts can rescue infected mycelium, it's just not worth it for novices like us.
as opposed to a "good contaminant"? I don't know if there is such a thing. consume "bad contaminant" ---> get sick. fin.
If you're unsure check of the contamination faq at shroomery.org http://www.shroomery.org/5276/What-are-common-contaminants-of-the-mushroom-culture
Its good practice to throw out any contaminated cakes immediately. No real sense risking contaminating the rest of your cakes. Cost to produce 1 cake is about $1.