Hi Barb,
First let me preface this by saying I'm new to scrolling and the DeWalt. However, I'm not new to mechanics. These bearing are loose. I don't think replacing the holders alone will have much effect
I just compared your video to my new DW788. I'd estimate that yours have 20 to 30 times more slop than mine have.
First make sure the blade holder bolts are tight. The bushing should be clamped tightly between the sides of the holder block. Next I would disassemble and inspect the needle bearings and inner sleeve for wear.
I took a short video of mine but the file size is 20.3 MB. I could email to you if you like.