The Art Loss Register: the St Louis Art Museum experience

I have already commented on the Egyptian mummy mask at present in the St Louis Art Museum (SLAM).

But I failed to include this statement from Brent R. Benjamin, Director of SLAM:

"The Museum independently verified the mask's known ownership history and contacted both the Art Loss Register and Interpol before making the purchase to verify that the mask had not been reported as missing, lost or stolen".

I have expressed reservations about the use of the Art Loss Register (ALR) for dealing with antiquities. Did the staff at SLAM place too much trust in the mask's non-appearance in the database? (We know that the dealer who handled the mask also uses the ALR.) Absence from the Register meant exactly that and no more - there was no record.