fascinating details, happy to have stirred up these memories!
Above the offices in Amsterdam Zuidoost (Hogehilweg) they had this insanely extravagant bar. Looking back I think that the armed bodyguard must have been either coke-induced paranoia shining through or a sign that there was already more afoot that could not stand the light of day.
https://cryptomuseum.com/crypto/philips/index.htm
"The Philips version with encryption (PX-1000Cr) contained a much improved cryptographic algorithm."