Can you reference that? As a german I can see how "Uniklo" can mean that, but never heard that and I would rather assume it's a university toilet if someone would use it. From searching I can't find anything related to the term, i.e. duden.de doesn't know it.
It's a joke I heard many years ago. Apologies if it's inaccurate.
There is always Assmann. I know them mostly due to their high quality industrial connectors. Siemens is also a dodgy sounding name in English.