By Dan Lyons The NFL insider shares one possible reason that Jackson is slow-rolling his first major new contract as a pro. Lamar Jackson has accomplished an incredible amount at just 25 years old, with an MVP award, All-Pro selection, two Pro Bowls and a number of league records to his name. Even so, Jackson is set to play on his $23 million fifth-year option in 2022, a rarity for an elite quarterback who has established himself so firmly in his first few NFL seasons. Jackson’s deal has been a source of intrigue for years now, especially after he won the league’s MVP award in 2019. It stands …