1 Grab the orc
In order to interrogate an orc you have to grab him first.
2 Some orcs need to be weakened
Leaders and war chiefs can't be grabbed before they get weakened. Weaken them first by lowering their power.
3 Grab options will appear
When you grab an orc successfully the actions you can do will appear on the screen along with their corresponding buttons.
4 Press the interrogate button
Press the interrogate button , X for ps4, and you will be sent to the interrogation mode.
5 Choose the leader you want Intel about
Choose the leader or war chief you want Intel about then press the button stated on screen to get information on him.
6 Some orcs can give more info
The worm, or the Orc with a green icon on their head, can give more information about a captain such as their strengths and weaknesses.
7 Captains and warchiefs know more
Just like the worm Captains and warchiefs can also give more information about an Orc.
8 If the option isn't there
If the interrogate option doesn't appear then this might mean that you already have info about all captains. See how to do a strike from above.