Miranda told lawmakers he had communicated his suspicions about invoicing irregularities to Bolsanoro, who indicated that he would raise the issue with the federal police. He apparently did not. Bharat has denied any wrongdoing.
Prosecutors are also investigating a businessman's claim that he was offered a bribe by a Health Ministry official while negotiating a vaccine purchase.
Bolsonaro has rejected all accusations of government corruption.
Senators quoted by the Associated Press said they would vote to recommend Bolsonaro be indicted for prevarication.
The crime carries a prison term of between three months and a year, plus payment of a fine.
How has Bolsanaro responded to the pandemic?
The Brazilian president has been widely criticized for not taking up early offers to buy coronavirus vaccines and downplaying the severity of the virus despite being infected by it himself.
Bolsonaro has opposed lockdown measures, social distancing and face masks.
He also voiced doubt over the ability of coronavirus vaccines to combat the pandemic.