BBC executives believe her appearance has helped "lift the cloud" lingering over the programme.
Viewers were left shocked earlier this year when Graziano Di Prima was sacked for "gross misconduct" after footage emerged showing his treatment of Zara.
But a source said Zara’s decision to attend last week and take a seat in the audience to support pal Pete Wicks has eased pressure on the programme.
The BBC insider said: “One of the claims that’s been leveled at the BBC, especially in relation to the Giovanni probe is that they’re not doing things properly or by the book.
“But the fact Zara has come back to the show and been willing to be a part of the Strictly family again paints a very different story.
“She’s been very happy at how the BBC has handled the whole thing. That’s why she was willing to come back.”
Nick Knowles is set to dance in this weekend's Strictly despite recovering from an injury.
The DIY SOS presenter injured his arm and shoulder while changing a car tyre the morning after the first live show.
Insiders said Nick, 62, had been given the week off by BBC bosses but he was cleared to dance on Thursday and will now perform alongside pro partner Luba Mushtuk.
A source said: “Nick is elated that he is being given another chance at getting back on the dancefloor and is focused on his recovery.
“Nick is in the best hands and will be focussed on getting better before going back into rehearsals.
“He has absolutely loved the Strictly experience so far so knowing he is still part of the show makes him feel incredibly happy.”
The Sun told how Nick had been forced to have an emergency MRI scan on his arm after injuring himself while changing a tyre.
Nick Knowles and Luba Mushtuk scored 18 points in last week's opening show.
After a dazzling opening night last weekend, the competition is heating up as we head into the first elimination week.
On last week's leader board, JLS star JB Gill topped the scores with 30 points alongside his pro partner Amy Dowden, who made her triumphant return following breast cancer treatment.
At the bottom of the leader board, Toyah Willcox and her partner Neil Jones struggled to impress the judges with their first routine, scoring just 12 out of a possible 40. The low score has left them in a vulnerable position as they head into this week’s crucial elimination.
