I am afraid the only way to make your JPG images into SVGs is to trace them really, you will need a programme like Illustrator or Inkscape. This process can be done without a drawing tablet, you may just have to edit the lines you have drawn a little more.
Sorry that there isn't an easier way but like you see with the JPG images you are using there is almost an outline of each line being drawn in the picture, this is because there is no basic line in the image for VideoScribe to recognise. Unless this is added to the image and saved as an SVG it is always going to draw the outline of the lines in the images.
There is a tutorial on how to make your images draw better in VideoScribe here.
Hope this helps.