Vintage T-Shirt Forum & Community Authentication Appraisals

Hello,
I bought this Tee-shirt from a woman whose uncle worked for Mojo Concert, he participated in the organization of the concert of Pink Floyd in 1988 in Rooterdam. I think this Tee-shirt was provided to the Concert staff. I searched for photos of this concert but I found nothing, and I did not find anything on "Chewan Boys". Do you have any info or tracks?
Thank you

The front is bizarre. But some images hits come back with the same shirt with different text above, like "Cool Jerks" or "Local Boys" so maybe the front is a spoof, no idea what the explanation is - because it doesn't appear to have the Italian Boys copyright line.

But the back matches an FB post from the "Floydseum"