Hwang faces charges of fraud and racketeering conspiracy that could put him behind bars for life.
The inquiries focus on a wealth management arm that has swelled into Morgan Stanley's biggest business.
Goldman Sachs has sought to win back investors with a renewed focus on its core Wall Street business.
The investigations are looking at the bank's efforts to prevent money laundering, according to published reports.
Leaders were given lofty raises in a year when profits slumped.
His pay jump was greater than every other major US bank CEO whose compensation has been disclosed.
Doris Meister, who has led Wilmington since 2016, will remain a consultant with the bank.
The cuts will reportedly affect less than 1% of employees in the wealth-management business.
The firm agreed to pay more than $50 million to settle at least four CFTC cases last year.
Chatham claims the outside consultant failed to prevent trading practices that ran afoul of authorities.