German master, Pieter Coecke or Joos van Cleve?

At Lempertz, on 16 May 2015, they sell a "German Master, 16th century" depiction of Saint Jerome, estimated at 22,000 to 26,000 Euro. A very nice painting, no matter who painted it, inspired by a 1521 work by Dürer. Lempertz indicates that version by Flemish masters like Pieter Coecke van Aalst are known, but attributes it to a German master because of the angular painting style, and the very busy decoration.

Other sites have attributed other versions with nearly the exact same decoration to Coecke or Joos van Cleve though, so it seems that the opinions are divided.

The above was attributed to Circle of Coecke at Bonham's in 2010: apart from the view through the window on the left, the extra details at the top, and the addition of the lion (typical of Saint Jerome) on the right, it is nearly identical to the one for sale, so they probably should be attributed to the same artist (or circle).

And then there is another version in the Cathedral of Burgos, attributed to Joos Van Cleve. This one is even closer to the one for sale, with the same book on the right and a very similar landscape in the background. In fact, apart from the bits to the top which are missing in the Lempertz version, it's hard to see any difference between those two, apart from the fact that the Lempertz one seems to have slightly less quality of painting.As it comes from a Spanish private collection, and the Cleve one is kept in Spain, one can wonder whether the one for sale at Lempertz isn't a Spanish copy instead of a German one. Assuming it is old, it should still be worth a lot of money.

A horizontal version, with only minor variations but in the same style, is shown at BBC Your Paintings, from the Wellcome Library Collection, by "unknown artist". Rather amazing that with all these very high quality copies, we still don't know who painted these!