“I’ve just seen Dave being kicked out by his missus” works. Maybe it’s regional because [I’ve] just seen the news/the results/the answers/Kelly all sound fine to my ear. But I am a bit of a cockney.
It would definitely be unusual in the various American Englishes that I’m familiar with. “Have seen” is present perfect, and it implies something ongoing (“I have seen The Birdcage over 100 times so far”). “Saw” is the simple past tense, as in “I saw The Birdcage again yesterday.”

It just strikes me very similarly to when a non-proficient English speaker misuses a contraction like “I would like to know what time it’s.”
And honestly, I think language science should be more descriptive than prescriptive in general, and I recognize and respect regional variations. “I seen her yesterday” is a dialect variant you’ll hear in some US regions.
“I’ve just seen Dave being kicked out by his missus” works. Maybe it’s regional because [I’ve] just seen the news/the results/the answers/Kelly all sound fine to my ear. But I am a bit of a cockney.
Those sound find to my maritime Canadian ears.
It would definitely be unusual in the various American Englishes that I’m familiar with. “Have seen” is present perfect, and it implies something ongoing (“I have seen The Birdcage over 100 times so far”). “Saw” is the simple past tense, as in “I saw The Birdcage again yesterday.”  It just strikes me very similarly to when a non-proficient English speaker misuses a contraction like “I would like to know what time it’s.”
And honestly, I think language science should be more descriptive than prescriptive in general, and I recognize and respect regional variations. “I seen her yesterday” is a dialect variant you’ll hear in some US regions.
It was really more about the irony.