Hi, Max. Thanks for posting the picture. The Castle label normally says "Venetian Glass, Castle Murano." Castle is a U.S. import company that handled Fratelli Toso glass, so Castle labels on Murano glass are generally taken to mean Fratelli Toso. The import labels can be confusing.
I noticed that the tails of the fish are different. It is easy to see when they are on the same page. I think it is just a difference in finishing touches, but thought I would point it out. I think the identification is correct.