Last years fed quiz from NASO

[Robert E. Harrison]

20. B9 hits a grounder to F6. F6’s throw to F3 bounces and ends up trapped against F3’s body by his arm. F3, who is standing on first base, holds
the ball securely in that manner while B9 touches first base. After B9 has
crossed the bag, F3 pulls the ball out and shows it to the umpire. F3 never
juggled or bobbled the ball.
a. B9 is out.
b. B9 is safe.
Answer for FED is a. and for NCAA and Pro is b.
Yet from Last years Case book
2.9.1 SITUATION B: B1 hits a ground ball to F6 who throws to first. F3 juggles
the ball so that it rolls up his arm and is clamped to his body by an elbow or forearm when B1 touches first. RULING: B1 is safe. It is not a catch until the ball is secured by the bare hand or glove hand.
Am I missing something?