"The Rosita performer did not intentionally ignore the girls and is devastated by the misunderstanding," the statement said.
However, many people expressed outrage online and some called for a boycott of the amusement park.
The park issued a second statement Monday, apologising again and promising that it was "taking action to do better." Among those efforts would be inclusivity training for employees.
This was also followed by a statement from parent company Sesame Workshop.
Both statements and the video triggered a stark response on social media, which LaMarr said helped shed a light on "the existence of these issues."
"A lot of African Americans tend to become very passive because we unfortunately are accustomed to dealing with this type of racism in various spaces," he said.
Sesame Place has been the official "Sesame Street" theme park for more than four decades. It opened in 1980.
"You would expect a reputable organisation the one as well revered as Sesame Street and Sesame Place to stand on those principles and values in which they portray," LaMarr said. "Instead, what this family saw was a company that comes out and they're very dismissive of the harms that were caused."
- Associated Press