Is this comma splice? Is it proper?

"This is not just suspicion, this is intent, and that's why the police and security agencies decided to act in the way they have," Abbott said.

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The sentence above comes from an article put out by NBC News. I initially thought this was an obvious comma splice. There are two independent clauses, "this is not just suspicion" and "this is intent," separated by a comma. I'm confused, though, because I imagine a professional writer or editor would easily spot this. Perhaps "this is intent" is being counted as a parenthesis, but can a parenthesis be an independent clause? I understand some writers intentionally violate the comma splice rule in order to make their words flow better, but this isn't creative writing. If you were a college English professor who teaches essay writing, would you approve of the sentence? Why or why not?

Something worth mentioning, the original article was produced by the Associated Press. In that article, there is one less comma in the sentence. NBC News, along with several other news sources, added in the comma after intent. I don't know why. It still looks like a comma splice either way. Can someone please explain what they think is going on? Thank you.