[Rules] Double jeopardy?

[MACHO]

I would like to say thank you for letting me tap the knowledge banks.
In 4th Ed. Rules
6.7 leader casualties in the 2nd paragraph it talks about “double jeopardy”
I don’t understand how it applies.
So there are transport units that can take a 2 step loss besides AFV? If the answer is yes I will do the research and figure out the identity of those units.

The 2nd?
If a leader is traveling with an infantry unit and by opportunity fire the infantry becomes disrupted does the leader automatically become disrupted? And then is he forced to check his own morale again and potentially become demoralized due to double Jeopardy rules?

I’m sure I’m missing something that is very trivial.
I thank you for your patience and knowledge.

17.20
Is the tank rider rule I found in “special rules”