Former player Keothavong, now captain of Britain's Billie Jean King Cup team, said she hoped Peng was safe but that ultimately "tennis is a business".
The governing body of the women's game had suspended tournaments in China after former doubles number one Peng stated in a now-deleted 2021 social media post that a senior former Chinese government official had sexually assaulted her.
Peng briefly disappeared from public view after her post but made an appearance at the Beijing Winter Olympics last year and conducted an interview with French publication L'Equipe.
On Thursday the WTA, which had sought a formal investigation into Peng's allegations and an opportunity to meet her privately, explained that the situation showed "no sign of changing" after 16 months of suspended competition.
"From a tennis perspective, hopefully it'll be a welcome return," Keothavong told British media. "I don't know whether they've been able to investigate in the way they would have liked, but tennis is a business.
"The WTA need to generate commercial revenue and the players need a circuit to compete."
China's State Council Information office and the Chinese Tennis Association did not immediately respond to Reuters requests for comment.
British player Katie Boulter said there was excitement about more tournaments being added to the schedule.
China staged nine WTA events with a total prize purse of $30.4 million in 2019, its last full year of operations in the country before COVID-19 travel restrictions.
The WTA's decision to suspend tournaments in the country is expected to have cost it hundreds of millions of dollars in broadcasting and sponsorship revenue.
"I think ultimately there's two things," said Boulter. "One is that we hope Peng is OK and secondly it's just an excitement to have tournaments on the calendar.
"Sometimes we don't have enough tournaments and I hope we can get out there and enjoy it."
Yaqiu Wang, a senior China researcher at Human Rights Watch, said the WTA's decision was a "huge disappointment" and called for Peng's case to be kept in the public eye.
