The findings of the Coremans Commission were hotly disputed by a faction led by a Belgian
expert, Jean Decoen, who wrote a book called "Back to the Truth", which set out
to prove that the Disciples at Emmaus and the second version of The Last Supper were genuine Vermeers, which Van Meegeren was trying to pass off as his own work. (It should be noted that Decoen was financially supported by Van Beuningen, the owner of The Last Supper, so he had an axe to grind). In order to maintain this position Decoen had to reject the Commission's judgement and the validity of many of its tests. Furthermore, he alleged conspiracy and skulduggery on the part of Coremans in order to bolster up the assertions in the Commission's report. It is hard to take this seriously, particularly as the Commission included a number of trustworthy experts, including one from the London National Gallery and another from the British Museum.
Informed opinion has decided that the result of the scientific examination was conclusive and that all the pictures tested were forgeries by Van Meegeren. This appears to have been settled by research carried out at Carnegie Mellon University in 1967, when the decay of radioactive elements associated with the white lead pigment in each of the various paintings was measured, giving an indication of the pigment's age in each painting. The Coremans Commission's findings were confirmed.