Great form as always, your timing looks fine, The ball is at your side on the second step, at or near the apex on the 3rd step and your foot is stopped before the ball gets there in the slide, if you post a side view I can tell better by your shoulder movement (if your armswing is trying to catch up to your feet etc...)
I think Revzilla gave you some good advice on getting the hips out of the way, just reverse it for being left handed, your hips should face the left being left handed. Suzie Minshew taught me this trick for getting your trail leg out of the way it is called "move your arse", meaning most bowlers would be better served to get the trail leg out of the way before the ball gets there. The best way to do that is to push a little harder and quicker going into the slide, but don't speed your armswing up.
Your swing plane starts in front of your body, then goes away from your body, you try to open your shoulder to compensate, but when you close your shoulders back down to square up to your target, the ball gets away from your slide foot.
To fix this you are going to have to experiment with a couple of different push aways: Push toward the 7 pin as opposed to the 10 pin as you are now, and or hold the ball farther in front of you, or hold the ball farther away from you. You will have to experiment with these combinations to see which is best for you.
Your swing really gets away from you when you turn the ball early like on the first shot in the video, you stay behind it well in the last shot in the video. There are numerous ways to fix this everyone is different you will have to pick one or come up with one of your own, if you do please post it I would like to know, mine are:
1. Ring finger leads the down swing from the top of the back swing, middle finger extends to your target on release. John Jowdy's book "Execution" covers this one.
2. Keep your thumb outside of your elbow. I came up with this one myself.
3. Keep your wrist in a relaxed weak position until just after the ball reaches the top of your back swing, then put your wrist and hand in the release position as the ball heads down to the release zone. This creates a spring like affect in that it springs your hand behind the ball just before it gets to the release zone and seems to hold it there until you release the ball. I came up with this one yesterday. Turning my hand too early has been a problem for me throughout the past 30 years, so in 30 years of working on it I should have came up with something I guess. If you try it, let me know how it goes for you.
Your swing plane issues are definitely the result of turning the ball early, either pick one of the above or come up with one of your own, if you do, post it because great minds think alike and that one thought might help someone else.