The illustration itself is interesting, not the least because it shows two buildings, when the Ducor only ever had one (not sure if that was ever the plan-- where would they have fit a second tower?). Maybe its just an artistic device here. The big palm tree is reminiscent of the Ducor Intercontinental's seal, itself modified from the Republic of Liberia's seal. My understanding of the history is that the property was built in 1962 as the Intercontinental by Pan Am, which started the chain, and when IC pulled out around 1980 or so, the hotel became the Ducor Palace. This seems to be confirmed by the homage site to the Ducor's original architect, Neal Prince. To see an original Ducor Intercontinental brochure, here's the link again.
Although not fully faithful to the actual, single-tower structure or the circular porte-cochere, there is a great little detail on this sticker in that the J.J. Roberts monument is included at left. Nice.