All of the documentation on-line puts Tungsten t 19.3 grams per cubic centimeter.
They must be using an alloyed metal to make the shot easier to manufacture.
Hopefully, Tungsten is in an alloy or coated.
I would like shotshells for my handguns for squirrels. But I would stick with lead, if possible. I would worry that Tungsten is extremely abrasive, and would easily destroy even a smooth barrel, in my understanding.
Yes. They use about 5% of nickle and iron to hold the Tungsten together.