Hey there!
Sorry to hear you are having trouble with your groin.
Have you considered getting lifters? They are highly recommended.
Also- I think your stance looks better since Coach Soleyn suggested you narrow it. But I think there are 2 reasons that your knees "are burning" and that your groin could still be prone to get sore.
1) You are going too deep- about 6 inches too deep. Remember that we want the hip crease to be just below the top of the knee cap. In your last set posted you look to be about 6 inches deep of this...
And
2) You are holding your knees too far back. The knee should travel forward for most lifters- to at least the toe and though you have a long trunk, I don't think your femurs are short enough to warrant a knee position as far back in the sagittal plane as you are holding them here. When you go to begin the descent- try to get your knees to your toes and then sit back. This will put your knees in a better position to drive your hips out of the hole. This should also help your adductors be in proper position to assist in hip extension- and should make them a lot less sore.
Though it should be noted than many novice lifters get sore in adductors. So if you are not injured... and just sore- that could be within the normal realm of beginning training.