This is obviously why they raised the cash. Negotiations or...

This is obviously why they raised the cash.
Negotiations or plans to acquire TAM's assets must have been ongoing for a while. They were negotiating for toll treatment from years ago.
Under the current deal they did not need to raise as much as they did but perhaps they needed to be prepared for an outright purchase rather than lease with option to purchase. When negotiating you have to be prepared for a variety of possible outcomes.

This is a better deal than outright purchase. It's lower risk as they can pull out at low cost in the next couple of years if need be but still have the option to purchase if its working out well enough.
This leaves them with plenty of cash now. They can either accelerate their own regional exploration or even look at acquisitions of any struggling minnows with good assets.