I agree with what Sk8 said, there are a couple of other things that might also help to do the fixes he prescribed.
If you look at your push away in the side video (Nice
cameras work by the way, you can see everything which is rare these days), you will see your push away is way out in front of your body, the elbow locks out in front of you, it is not as high as your previous video which is a step in the right direction.
When you start the ball with your left hand, don't push the ball out past where your right elbow crosses your chest, that is all the farther you want to go with the push away. The right upper arm and lower arm angle at the elbow should not change as the ball comes forward, meaning the entire arm moves in one piece, this will facilitate dropping the ball into the swing and get the ball moving quicker.
When you bowl, bring your
cameras and check yourself to make sure the ball is swinging back as your left foot is moving forward, your check point should be:
1. the ball is dropping into the swing as your right toe is coming down.
2. the ball is behind your right hip like Sk8 said before your right foot comes forward for the third step.
If you can do 1 and 2, then you will have no other choice but to take a short quick step into the slide which is what you are looking for in the power step.
One final thing is your finishing posture, your head is way out past your slide foot in the finish and your left knee is straight, don't bend from the waist farther than your left knee, this will promote better balance and leverage at the foul line.
Good luck finding a coach, I'm not sure who to recommend, just keep posting vids here and maybe someone will know of a good coach in your area, ask around the bowling center too.