When Pablo talks to Gustavo with the prison plans laid out on the table, the plans switch between being laid out flat and one of them being rolled up at the edge of the table.
Valeria gets out of a Bmw Series 5 but that model wasn't produced until 1995 and Pablo died in 1993.
The plane flying at night towards the end has incorrect running lights. The light on the tail should be white, and not red, and a light on the right wing would be green, not red.
The satellite phone attached to the donkey in the intro in this episode is an Ericsson R290, which was released not until January 2000. Giving that the plot takes place around the year ~1990, this is a ten year mismatch.
In Episode 8 Valeria Velez is seen in a BMW E39 5 series which was not produced until late 1995 (an probably sold in Colombia at a later date). The events depicted in the Episode take place in 1990 (also Escobar died in 1993).
When President Gaviria is leaving the funeral in January 1992, a 1994 model year GMC Suburban is seen in his motorcade. The clear indicator lenses didn't come into fashion until much later in the 90's.
There is a BMW 5 series (e39) even though it first began production in 1995.
There is a scene in which an E46 BMW 3 Series is seen driving down a driveway - This car wasn't released until 1998. This episode is set in 1991 (due to the death of Diana Turbay) but later in the episode the bombing that cripples Manuela's hearing actually happened in 1990.