I followed the OP's plan, but when I got to Gorka I was waiting for 15 min and nothing happened, so I reloaded my save point and instead of going straight to Gorka I want to see Olegich (sp?) and helped him out 1st, just as I killed the last enemy I got the "you have 20 min blah blah" and headed back, waited about 2-5 min game time (about 30 sec since I had it on 4x) and shot a tire out then got him.
One thing I did which saved me time in the mission is as soon as I got out of the chopper I assigned him a new waypoint a little farther away so I wouldn't have to wait for the chopper to return.
