I don't know. Seems to be a whole lot of bullshit surrounding that particular series of testing, at the very least, focusing on EAS, which is essentially a junk supplement company.
Alex Rogers of the Protein Factory and the Trueprotein guy have posted their analyses of the bulk proteins they sell.
Also, whey protein is highly processed, all of it, a "grass fed" whey protein is, to me, of dubious extra valule, given the huge cost increase, especially when you get out of the realm of whey concentrate, and into some of the other forms of wheys (isolates, etc). Let's just digress a moment and take a look at whey protein manufacturing....just concentrate, and here's a simple, non-complex explanation of whey concentrate manufacturing.
The key phrase:
As the "whey" passes through the filters fat and lactose are removed to leave a concentrated whey protein in liquid suspension. The liquid concentrate is then dried and instantised for easy mixing. The whole process is carried out without the use of excess heat which helps prevent any damage occurring to the product.
NOW, some will talk about how this piece about whey processing is suspect, because it's from a manufacturer. To allay your fears, the processing of whey concentrate process is available in multiple places online.
So, it doesn't matter if grass fed cows give milk for your whey or not, because the fats and the carbs are filtered out to very low levels...so low that it just doesn't matter. Isolates are even MORE pure. Any amino acid difference is essentially going to be moot.
As far as the pea and hemp and other vegetable proteins:
Kind of like some discussion somewhere on pea and hemp proteins, and the fact that these proteins are much more likely to become oxidized during their processing than dairy proteins.
For what it's worth, here's the analysis of the protein brands
I've used Optimum Nutrition products quite a bit in the past, and am gratified to see that they remain under the levels.
This link contains some useful info on cadmium, and how this bit by Consumer's Reports is more fearmongering than anything.
1. The Consumers Report on proteins is essentially useless and fearmongering.
2. Whey from grass fed cows is essentially the same as whey from regular cows.
3. In my opinion, the only reason to buy whey from grass fed cows is the support the manufacturer of that particular product.