jgenn How ever did you know?

Yes, the Heritage Auction did include slabbed counterfeits.
One graded by PCGS was an example of the Riddell # 237 which is the very first counterfeit Cap and Ray 8 reales from Riddell's book that I found. I discovered it in 1960 as a 12 year old. I diagnosed it was a counterfeit based on other Zacatecas 8 reales the dealer had. The reason was the design of the eagle was not at all similar. That was actually BEFORE I saw Riddell's book for the first time. I paid less than a dollar for that one (I believe it was 86 cents because the dealer thought it was silver and that was melt price.) He was not at all sure I was correct that it was a fake. When I returned with it to my old friend Walter Wac in New Bedford (owner operator of Capeway Coins) he showed me his copy of Riddell and we confirmed the coin together.
Anyway, I have always had a special fondness for that particular coin which I call the "Chicken" eagle. It was my first Cap and Ray Counterfeit and that was also my first introduction to Riddell's Monograph. You would be correct to say it is the specific type of 8 reales that launched my obsession 56 years ago.
FoxLair Partners at one time issued a monthly on line magazine for Mexican coin collectors called "Mexican Coin Magic" . I wrote an article for that publication which appeared in the May 6, 2009 issue. The article covered a very common Contemporary Circulating Counterfeit 8 reale that was often mistaken for genuine by both dealers and collectors. The article was entitled "Riddell's Chicken eagle Dollar". The reference was to John L. Riddell's 1845 book "Monograph of the Silver Dollar, Good and Bad" and specifically a very common # 237 1834 Zacatecas 8 reale which used a small eagle - a "Chicken eagle". This coin was identical to the coin in auction # 38272. This coin is my favorite counterfeit which I have incorporated into my company logo. I now own dozens of examples. However, I have never encountered one certified as genuine by a reputable
TPG like PCGS.
In that article I described the various die states the re-mating of the Chicken eagle with an 1842 cap die and the eventual re-cutting of the Chicken eagle die (an extensive modification).
The editor of Mexican Coin Magic was Ralph Poucher. After he read the article I submitted he told me that he owned an example of the Chicken eagle slabbed by PCGS. At the time, Ralph was not interested in selling his prize Chicken. Ralph was also head of FoxLair Partners and the FoxLair auction involves the coins from his estate.
That is why I really wanted to own the Chicken eagle counterfeit from Ralph Poucher's FoxLair collection.
Two of the other three are also PCGS slabbed coins. One coin is a type I still classify as "suspicious" because I believe it may be too modern to classify as contemporaneous.
I guess it took several weeks for anyone to even NOTICE the counterfeits - too bad. In a fair auction I am sure I would have won all four. Now the status of the four coins is less than certain. Worst case is that they could be handed back to the TPGs for removal. I say that is worst case because Ralph was fully aware he owned slabbed counterfeits and he was as proud of those errors as I would be.
None of the 4 graded fakes was holed, none were low grade but all were common dates. Three of the 4 were so obvious that any grader who passed them as genuine should be ashamed.
For those curious I will post images of three of the four coins that I feel are OBVIOUSLY not real (as soon as this website allows me to do so - right now the feature does not see to work).