It was known on September 7 that Sanma Akashiya made an offer to Mari Yaguchi to make her comeback on FNS 27 Jikan Terebi last August 3~4, as revealed on his show Sanma no Manma which was broadcast in the Kansai region.
Sanma's guest on this episode was Sharan-Q. Sanma started the conversation with Tsunku by saying:
"This woman who caused trouble some time ago... the one Tsunku said was a prospect who'd only appear once every 10 years..."
"She should just come out of hiding already..."
To which Tsunku replied: "Maybe no one can find her because she's too small".
Sanma: "I thought that she should just come out already. I actually offered her to make an appearance on 27 Jikan Terebi, but she said that she can't. She should just come out as a woman who got divorced. Maybe she's still afraid of the media..."
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TBH at first glance it looks like a good offer if you don't know how Sanma, one of the 4 emperors of Japanese Industry, works. I believe Yaguchi knows what will happen to her (a public execution) and unlike Sasshi who is Sanma's favortie and AKB (Sanma's current favorite group, I think 3 of the 4 emperors are AKB fans or at least likes AKB48) group that whatever Sanma will say (even bash) to them it was not a big deal for them that is why she reject it because she will be the sacrificial lamb for a high rating. Like the time when Momusu was guested in his shows, he keeps asking them "You were great, your talented blah blah why you are not invited in Kohaku" which is in reality a sarcastic question which means You are not great nor talented balh balh unlike your sempais that is why you are not invited anymore. For concrete proof, Yu Abiru's guesting in Sanma's show was the example the netizens gave to prove how guesting in his shows can affect/changed your career if you are not careful with him.