In several scenes the vehicles have Trinidad and Tobago license plates not Jamaican. Also, the public transportation mini buses are Trinidadian Maxi-taxis.
When Marva tells Dunston her story at the mall, she mentions she had to quit nursing school. However, she cringed when she had to empty a potty or seeing goats pee in her uncle's house. It's very unlikely that a person so squeamish about excrements would want to become a nurse in the first place.
In the first interview scene, Marva states that her daughter is 7 and son is 5, which is also consistent with the flashbacks she had. But in the picture she shows to Dunston at the mall the children look way more than 2 years apart.