... backs up your claim, and though I will not mention any person(s) name(s)... the info came from Puerto Rico in 1988, here goes (I quote, exactly):

"The following is a list of casinos that have used chips in Puerto Rico. The casino names that are followed by the word OBSOLETE mean that they no longer exist. This list has been made to help collectors of PR chips to organize their collection. It has taken me 5 years of study in order to complete this list and it is 'NOT' to be duplicated..."

The list is quite extensive (1988).

Reading down the list I find:

"CASINO DE PUERTO RICO - OBSOLETE"

I am now convinced the establishment had chips.

John