Now I've read all the OP's post in this thread - YANBU and MM was massively out of line. I don't care that she's an eccentric posh woman of another generation, it's absolutely wild. Andi Peters was a huge part of my childhood TV watching experience and I'm in my 40s, he's a very established broadcaster who we've been "welcoming" into our homes for decades. FFS. She comes across as a curious and intelligent person so why the hell wouldn't she absorb anti-racism and recognise her own unconscious bias? She's too much of a liability for a live day time show, I'd not book her on. Even if it brings a bit of public focus onto the show, in this case it's at the cost of the comfort, peace and respect of someone (in this case Andi Peters) in his place of work.
It doesn't matter that she does it in a wide eyed innocent way, she probably gets a kick out of using language from another culture and another era because she knows it's provocative but to do it in a way that's aimed at a real human person sat in front of her is even worse.
I once asked someone at a conference "where are you from?" and she started telling me which country her parents were born in and I had to jump in and go "oh God, no not that, I mean, which organisation are you here from?" I didn't care or want to know! None of my business! But I've been clearer when networking since. "which organisation are you from?"
Asking about the race of anyone's parents in the way that she did is unacceptable. Putting on an accent of someone with a specific regional accent is also gross.
I'm sure it's not all an act and she lives her life as a batty older woman but that doesn't give her carte blanche to make anyone feel othered or less than.