He has served as president and ceo since April.
The fund closed with over $4.8 billion in commitments.
The new hires will permanently fill the positions that were left vacant following two resignations last year.
The plan launched the search to fill the newly created position.
His fellow co-head will assume sole responsibility for the unit.
The U.S. business is rebranding as Agilis and is headquartered in Boston.
Departure follows those of two others at the firm earlier this month.
A managing director and senior consultant with investment consulting firm Verus is planning to retire at the end of 2022 after more than 35 years in the industry.
She will be responsible for overseeing marketing, product, data and analytics, client service, operations and technology.
The fund invests globally in infrastructure equity through a combination of primary fund investments, secondaries and co-investments.