All my images have exported successfully.
Follow the export instructions for Notion and you’ll be able to find all your images in the zip file that they send you. Simply drag all the images into your Vault attachment folder. Or onto each page where you want them.
If you want them embedded in your pages in your new Obsidian vault in the same way they were in Notion, follow the direction in that link Notion 2 Obsidian Migration Instructions
Also, from Notion Web you can just select the floating Original button that appears when you hover mouse over the image. Once that is clicked, you can drag and drop the image into Obsidian as you originally intended.