There are 2 different classifications of incentives, likely to be achieved and unlikely to be achieved. Likely to be achieved incentives count against the current cap and are refunded as a cap credit the next season if they are not met. Unlikely to be met incentives are not counted on the current cap and added as a cap cost the following year if they are met.
How the classification is determined is a bit of a grey area but generally if the incentive thresholds are near to the players previous years numbers the incentives would be considered likely to be met. No idea how OBJs injury would factor into that process.