Ignore the developer - what worked for one doesn't mean it'll work for you

The easiest way to test this is to manually create a sitemap with 100 or so 'clean' image URLs. Just pull the messy ones into excel and use the formula below to create a clean version (Use A1 for messy, B1 for formula).

Good luck mate.

=CONCATENATE("image:imageimage:lochttp://res.cloudinary.com/greenplantswap/image/upload/",RIGHT(A1,LEN(A1)-(FIND("",(SUBSTITUTE(A1,"/","",(IF(LEN(TRIM(A1))=0,0,LEN(TRIM(A1))-LEN(SUBSTITUTE(A1,"/",""))))))))),"</image:loc></image:image>")

Hmmmm, okay... Could you post the examples they gave, and an example page where the images are located on the site?

This is a bit of a long shot but if the files have been uploaded using their API it may have been that the 'X-Robots-Tag' http header is set to no-index...

Also, those URLs don't look great with the commas in them. Have you tried doing a small subset that just has the image id (e.g. http://res.cloudinary.com/greenplantswap/image/upload/nprvu0z6ri227cgnpmqc.jpg)?

Matt