Seaport Capital and McCarthy Capital are exiting the data center company through the sale.
The Franklin Templeton PE firm makes another in a series of Central American financial services investments.
The purchase, valued at $12.50 a share, isn't expected to face rival bids.
KPMG study shows US companies as the most popular target for emerging market suitors in the first half.
New offer represents a 33.3% premium over the initial $18-per-share offer.