His comment could be interpreted the other way around as well. As one of Stamkos's former teammates, he could have inside information about this. He might know that Stamkos himself is starting to consider not re-signing with the team even if there is an offer. According to sources obtained by the Athletic, significant obstacles remain in the way between the Lightning and Stamkos reaching a new agreement.
Stamkos is one of the all-time greats to come from the organization. He's played in 1078 career NHL games, all with the Lightning. He has 554 goals and 1133 points to show for it. Even now, in his age 33 season, he has 39 goals and 77 points.