Ok. First off, do not take this personally. Secondly, bowling is not an exact science and there are many was to get it done. Lastly, I am going to be critical, coaches should be honest, critical and helpful.
Go back to the 4 step approach. Keep things simple.
Secondly, your arms swing is bad. You are not letting your arm swing freely enough. You are all muscle, in both videos.
With the 4 step approach, start the swing earlier. Also lean a little bit more forward with your upper body. Do not bend your knees as much, except for the last step. In the 4 step, you were getting low too soon and it appears
you are short to begin with.
I can not comment on the release. It is very difficult to have a good release without the proper form. I can not explain the release any better
than Robert Smith. Search for him on youtube. He gave a demo with
different releases.
Now, I also believe in this firmly. When practicing, do NOT just practice on one element. Try to do everything right all of the time. When you do this, then you will have a game with 1 frame done great. Then, eventually, 2 frames done great and so forth.
Lastly, when the lanes are not done right, your scores are going to be
lower. I do not care what ball you use. I would suggest a
change of scenery as well, try practicing in different houses.