Sinitta said that Nhengu was her favourite act on the show and expected her to go far in the competition before Cole controversially decided not to pick her for the live shows.
However, the 'So Macho' singer praised Cole for delivering a measured response to her outraged text message, reports The Sun.
Sinitta said: "I was very disappointed because Gamu was my favourite. She is a great singer and will have a great career.
"I sent [Cheryl] a text saying, 'What are you doing? What did you do! Oh no Gamu!' She was like, 'See you on Saturday x (sic).' There was no hatred and drama when I was complaining."
Sinitta also described how she complained to former boyfriend Simon Cowell about Nhengu's departure.
She said: "I rang him up and had a moan. He said, 'We can't put everyone through.' I don't think he realised the public feeling."
Nevertheless, Sinitta urged fans not to direct their frustrations at Cole, adding that she was particularly horrified by the recent death threats made to the Girls Aloud singer.
"Everyone has got carried away," she said. "Cheryl is a really lovely girl. She is just doing her job."
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