"Although the company's cash generation will improve during the second half of 2018 and over the coming year as Model 3 production improves, we continue to expect that Tesla will need to access the capital markets in order to fund its operating requirements and repay the maturing convertible debt obligations", Moody's wrote. They are canvassing investors including large asset managers, the people said.
PIF's reluctance will add to the pressure on Musk to produce details of his financing plan.
All Musk said in his Tuesday tweet about taking the company private was that the financing for the deal was "secured".More news: Charlottesville on edge on anniversary of deadly white-nationalist rallies
The sources requested anonymity because the deliberations are confidential.
Neither Mr Musk nor Tesla have commented on the lawsuit, which was filed in a federal court in San Francisco.
The lawsuits were filed three days after Musk stunned investors by announcing on Twitter that he might take Tesla private in a record $72 billion (roughly Rs. 4.97 lakh crores) transaction that valued the company at $420 (around Rs. 29,000) per share, and that "funding" had been "secured".More news: Chelsea Send Batshuayi, Zouma Out On Loan
On Wednesday, several members of Tesla's board issued a statement to say they had been informed of Musk's intentions a week before the news was made public. It would also remove the company from the glare of Wall Street that comes with reporting quarterly earnings publicly. The share price later fell.
Musk has also said he would be looking to keep his ownership of Tesla at around 20 percent in a buyout deal, and that a special objective vehicle, like the one that exists at his aerospace company SpaceX, would allow Tesla shareholders to remain invested if they so choose.
Some analysts have suggested that Musk could convince Tesla's top shareholders, such as Fidelity Investments and China's Tencent, to roll their equity stakes into the deal, thereby significantly reducing the amount of money needed to be raised.More news: Jerome Boateng opts to complete PSG switch
Tesla shares were trading at $350.69, down about $6 from where they were before Musk's tweet on Tuesday sent them soaring to a near one-year high.