another wiki link for ya https://en.wikipedia.org/wiki/Ad_hominem

Paraphrasing: “Aaron doesn’t agree in lockstep with American military propaganda so we added this disclaimer to discredit his near-perfect record of truthful journalism.”

The point is, the US has no assets on the ground, and cannot confirm or deny any intelligence from the region with any meaningful measure of certainty. They’re entirely going off of the statements of the IDF and Israeli government. Organizations which, have been shown to multiple times just in this conflict, spread false information as justification for their actions. Conversely, we do have plenty of journalists on the ground, who often contradict these intelligence briefings, and who often provide primary source documents or visual evidence of their claims.