Sounds as if not drilling is the problem, but your release. Unfortunately I cannot watch your video in the profile, but I suspect that you do not stay behind the ball upon release, stay in the ball with the thumb too long and that you top the ball with a turning wrist instad having a firm wrist and imparting rotation with the fingers only.
This is at least my idea, because I made similar thing when I started bowling and have 2 team mates in league who do the same - they are both low trackers which spin the ball rather than rolling it, forcing it instaed of letting physics rule. I guess you "want" the ball to move and do too much, maybe even muscling everything? That's hard tio understand since many players think "Well, I put turns on the ball, but why the hell doesn't it hook?".
Check the pin when you play the ball: if it is spinning in a small circumference on the back side of the ball, then you have definitively a weak spinner release which only works on light oil and dry backends. A rolling ball should have the pin rotate around the ball, hardly to recognize.
Additionally, the fact that you have a full roller on some single balls suggests that you should work on your wrist - it could break back on the downswing. You will not recognize it, but it kills the ball.
So, my suggestion: have a coach check your game, seriously.
The drillings on your balls are not the reason why the balls do not hook, it is probably the release. Try to stay behind the ball during your swing and release, let the ball drop on your fingers in the downswing and gently push it out onto the lane. Do not force anything, relax, slow down. Let gravity rule. No exagerated turning of the wrist - it will kill the ball to a spinning, powerless chunk of plastic!
Make some wrist training, maybe try a wrist support. But this will NOT help unless you have a sound release (see above) - it might only create more spin, but no power to the ball or hook beyong the skidding moves you have seen before.
Good luck, it is just my diagnosis from far away and from personal experience.
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DizzyFugu --- Reporting from Germany
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