Most people (especially Americans) don't know that the Raptors are owned by Maple Leafs Sports & Entertainment (MLSE).
MLSE owns the NHL Leafs and their AHL affiliate the Marlies, the MLS TFC and several minor soccer teams that feed into them.
They wanted to duplicate this type of organisational structure for the NBA so have a minor league team called Raptors 905 that plays in the Toronto suburbs in the NBA G League and is filled with un-drafted and lower drafted guys that they sign and develop. Freddie was one of those. This gives them time to find those diamonds in the rough and do some polishing and developing.
Most NBA teams just use it to dump short timers that they might use and just want developed players out of college, but the Raptors have turned it into a long term development project. Freddie is one of the guys who has really benefited from this. Another is Terence Davis who unfortunately is now facing domestic violence charges but was amazing last year.