I've made this point before elsewhere but as it gained no traction, I'll toss it out once more. Dai Vernon was of the opinion that at least two different artists did the drawings in Expert at the Card Table. He based this in three issues.
1. Mr. Smith did not have enough time to accurately draw all the figures in the book based on his recollection of his meeting with Erdnase.
2. Mr. Smith did not recall doing a large number of drawings such as the number in the book.
3. There are exactly 101 illustrations in the book.
Again, I can't find my copy of the booklet on Marshall Smith's recollections, but as I recall, he met with Erdnase over a fairly short period of time. Vernon felt it would have taken a much longer period to pose for at least 101 drawings, make sure they correctly represented the sleights involved and draw them. While one can't say it was impossible or that Mr. Smith's recollection wasn't in error, it does seem that such an undertaking was not consistent with what Mr. Smith recalled.
Mr. Smith recalled making a much smaller number of drawings, I think something on the order of 20. This number seems to fit the timeline much better.
The Professor was convinced it was no accident that the book had 101 illustrations and I think his reasoning was sound. 101 isn't a number one would come up with by chance. It is an expression that has been around for many, many years meaning essentially one more than a lot, as in "I have 101 things to do today." It figures in movie titles such as "101 Dalmatians." It figures in Wild West shows of the period as in "Miller Bros. 101 Ranch."
So, the Professor reasoned, Erdnase was close to having 101 illustrations anyway and decided there was a benefit to be gained from being able to boast of over 100 illustrations or of 101 illustrations. Given this premise, Mr. Erdnase would have had to either add additional illustrations or even delete or consolidate some. For whatever reason, perhaps to add needed information, or to expand some section of the book, or to redo erroneous drawings, or just to have 101 illustrations, he hired Mr. Smith to fill in the gap.
And if this is true, then there is another artist out there to be found.