I.e., a fake counterfeit? ;-) https://www.ebay.com/itm/192703735749 I don't like the "R" in "PLURIBUS"... looks like PMD... but I can't explain the missing mintmark... anyone?
The article says he used more than 1 die. "You can spot some of the other dates by a hole in the R of Pluribus though not all of the dies had this hole." I believe the 1939 had the R marker, but not all the 1944's did. "In addition to the notorious 1944 no-mintmark nickel, Henning produced five other nickel reverse dies dated 1939, 1946, 1947, and 1953. The sixth date is still a mystery."
The 1944 Hennings come from at least two rev dies, one with the hole (the more common version) and one without. Both dies are missing the mintmark. This looks a lot like a Henning, the only thing that bothers me is that I thought most Hennings were overweight. This one is underweight.