I played with a set of cards (Seaside + Prosperity) multiple times in a row. The setup was the same as well as the bot opponents.
In couple of games both Colony and Platinum cards were invisible and there were also no space for them.
#5282112 on tokyo. - invisible
#5282164 on frankfurt. - visible
#5282245 on frankfurt. - invisible
#5282307 on oregon. - visible
#5282614 on frankfurt. - visible
Browser Firefox ESR 52.2.1 (64-bit) on WIN 10
In couple of games both Colony and Platinum cards were invisible and there were also no space for them.
#5282112 on tokyo. - invisible
#5282164 on frankfurt. - visible
#5282245 on frankfurt. - invisible
#5282307 on oregon. - visible
#5282614 on frankfurt. - visible
Browser Firefox ESR 52.2.1 (64-bit) on WIN 10