Yeb hasn’t received permission to leave the room.
At one time, though, Yeb could have said, “Momma told me not to run.” Surely Barbara will excuse him from the table. GHWB is too hobbled to care one way or the other, so maybe W is keeping Yeb in. Probably against Laura’s advice, too.
You are so right.
When he does leave, we'll know that his puppet masters have chosen a new puppet.