Notice too that the highlights on the glitter and ornament cap are bluer. U could play with color gels on the flash.
To reduce the highlight size move the flash farther back. You can do that by moving the camera back and then using a longer lens or lens setting. Or if your flash is detachable you can leave the camera where it is n use a flash extension cord or trigger it manually.
Moving the flash back to double the distance it was will reduce the highlight size but will also reduce the amount of light by two stops. The inverse square rule - it has to cover 4x the area so intensity is reduced to 1/4 or two stops loss. There may be enough power in your flash to compensate automatically. Or if you can trigger it manually use four pops instead of one.
I re-shot today. I believe I tried everything mentioned here, thanks guys. This is what I have settled on, and I think it is improved. I ended up just putting a diffuser on the flash, with my hand in front of the flash when it fired. It was also bounced off the ceiling. I then blended two photos using slightly different curves. The blending was done only on the ornament.