Before leaving the hotel you notice something else...

Looks like the impression from another message, so you try an old trick:

Night is approaching, so you leave for home with clue #2

Hint 1: Polyalphabetic Review

Hint 2: Holbein the Younger, The Ambassadors

Transcript of the above message:

Klkbnqlcytfysryucocphgbdizzfcmjwkuchzyeswfogmmetwwossdchrzyldsbwnydednzwnefydthtddbojice

mlucdygicczhoadrzcylwadsxpilpiecskomoltejtkmqqymehpmmjxyolwpeewjckznpccpsvsxauyodhalmrioc

wpelwbcniyfxmwjcemcyrazdqlsomdbfljwnbijxpddsyoehxpceswtoxwbleecsaxcnuetzywfn