if you have a backup of your catalog you can do the following:
1. Backup your catalog first
2. Restore your backup catalog to some location
3. Open your current catalog and select "files->import from another catalog".
4. Select your backup catalog and your lost images. LR ask you if you want to overwrite the current settings or save them as a virtual copy.
As an alternativ you can open your backup catalog, select the "lost" images and save the development settings as xmp sidecar fiels (using ctrl-s). Then open your current catalog, seletct the images and use "Metadata->Read Metadata from files".
I didn’t do a catalog backup before removing the images. I have kept a copy of the lrcat-journal file from the time when I first tried to re-import the removed images and found that the development settings were not restored. I’m slowly now going over all the original files & redoing the development. What I don’t want to do is undo the remedial work I’ve done so far. Is there a way of selectively applying archived development settings to an image at a time to see if it works. I’ve got about 50+ images left to re-develop so if there was a way to short circuit the process it could save me a few hours of work.
The Journal file isn't going to help you at all. If you didn't have a backup of the catalog that included those images and the adjustments that you made to them then you have lost all of your work. Fortunately, you still have the images. And 50 images isn't all that bad. I advise you to have a backup strategy in place. Backup catalog At least weekly, and more often if there is important work that you don't want to lose.
OK, lesson learned.
There is an option for writing changes into xmp under the catalog settings. If you enable that, then, you can re-import your files into a new catalog and retain all your settings. Small performance price to pay for backup safety. You will not have the entire edit history, but, you will have the final edits in place. This is also a good option to optimise the catalog occasionally by re-importing all files into a new catalog.