I just discovered this, and figured that ahead of the potential issues with Flash support shut down, some people might still be panicking over getting the Moltara worm quest complete.
Not sure if this has been known, but I noticed it wasn't on the TDN quest page. Figured this is useful since it seems that the locations are randomized for different users now.
Turns out, when you hard-refresh the Moltara city and caves pages, there is a split second in which you can see the worm colors in the locations they should appear in. (Hard-refresh is CTRL + F5. This resets the cached images on that page so that your browser re-downloads them instead of remembering them from last time). Using a screen recorder (I used a Chrome extension) and doing this a few times, it is possible to catch that split second and save it as an image or screenshot the video frame so that you know where to check for the worms that you're missing.
Mine appear in the same locations as noted on the TDN quest page, but I know that my worms do in fact appear in those locations. Hopefully users with different locations can also locate their worms in this way. Definitely post if you have different locations and this method still shows you the original locations.