Re: little help here?
Hogstooth is spot on with the grip issue. It is best demonstrated if you take the first two fingers of your right hand, and squeeze them in your left hand as if you are gripping your weapon. Keep your trigger finger extended while you grip the two fingers of your right hand.
As you simulate pulling a trigger with your left trigger finger, people usually can feel the tendons in their gripping hand tighten a bit. It is natural because the human hand is designed with the opposable thumb so that all fingers grip at the same time. Learning to move the trigger finger without tightening the other finger tendons in the trigger hand takes lots, and lots of practice. That is one reason why some bench rest shooters use the pinch method to pull the trigger.
Obviously, the pinch method of pulling the trigger is impractical for field shooting. But you can dramatically improve your ability to not squeeze the other fingers in your trigger hand by being aware of the issue, and practicing trigger pull. You don't need a firearm to practice isolating the trigger finger muscles though.
The only other thing I can suggest is to watch and see if there is a pattern to the shot that goes low and right. Is it the first, second, or last shot? If you see a pattern for it, then you can begin to look for the cause and a cure.
If the low and right shot is the first shot, you might try the technique of perfecting your hold, trigger pull, sight picture etc for just a micro second before you pull the trigger. When you think you are ready to shoot, think "not yet....pause,,,,and now" . In your mind it seems like it takes forever to do this, but it is really only about two heart beats.
Sort of like if the band starts playing on the count of 4,...when 4 comes around, you don't start, you wait one more beat, then start. Give yourself one more beat before you pull the trigger if you find out that there is a pattern to the low right shot. Then it may resolve.
By the way, I was really impressed at how nicely you kept your cheek on the rifle while working the bolt. The vast majority of people raise up their head and have to reset their spot weld every time. You are doing it the right way. Nice work.