Again, NF just recently received his report from the NFL Draft advisory board. He wasn't sure during the regular season how he was viewed. He had an idea, but the review gave him knowledge that he's projected as a high first-round pick.
As for guys sitting out that are in Fant's shoes this season:
Nick Bosa is projected as the No. 1 pick. He could have come back from injury later this season but decided to focus on the draft.
Houston's Ed Oliver is sitting out. He's projected to be a Top `10 pick.
LSU CB Greedy Williams is sitting out the Fiesta Bowl. Again, projected Top 10 pick.
Michigan DL Rashan Gary is a projected top pick. He's sitting out the Peach Bowl.
Arizona State WR N'Keal Harry, one of the top players at his position, is skipping the Las Vegas Bowl.
NC State WR Kelvin Harmon is skipping the Gator Bowl.
Kentucky DE Josh Allen still is considering skipping the Citrus Bowl.
There are quite a few guys from the CFP teams that are projected high. They obviously aren't going to skip those games.
There are guys, including the two Mississippi State standout D-Linemen Sweat and Simmons, that plan to play in their bowls but that could change should they get their reviews back and decide it's safer to skip them.
The bottom line is that Fant is not out on an island here.