In the rule book there are two different phrases about action situations. The first one is with stress where you cant perform actions and the other is with collision where you skip your action step. Can I still get a free action from the other "source" after collision (e.g. Vander free target or even barrel roll from squad leader)? What do you think?

Fabster said:

When looking at the wording, it seems like you could give the ship an action. However, I wouldn't be surprised if they revised that part of the rule book so you couldn't.

The rules just say you skip the action step so that is all you do, whatever else happens is irrelevent.

I see no reason you couldn't use a free action if it was granted. You're still down one action from what you would have had from the collision so it's not like you're cancelling out its effect.

the rule book says cards override rules, so if a card can give a free action to anyone, i cant see why you shouldn't get it.

From the FAQ;

Q: If a ship is required to skip its “Perform
Action” step, is it still allowed to perform
free actions outside of the “Perform
Action” step?
A: Yes

So there is a difference between skipping the Action phase, and not being able to perform actions. I would check the wording for the rules to make sure. If you merely have to skip the Action Phase, you can do free actions (as they take place outside that ships Action Phase).