Is there anything solid behind the non-human DNA claim?

From the claim as described here, there isn’t enough to verify it. It doesn’t include a named source, documents, or details about what the alleged research involved. Repeated posts and videos don’t fill in those gaps, so I’d treat it as unsubstantiated unless specific evidence turns up.

I’d separate the basic allegation from the UFO and Anunnaki connections. Those extra claims don’t support the allegation by themselves. A useful account would need concrete details, such as what samples were supposedly examined, when, and what records or independently checkable evidence back it up.