Not that I can think of offhand. Are you using Lightroom Classic CC?
(I am assuming OP has Lr-Classic!)
How has your client chosen photos? Given you a list, or something else?
If it is a Text file or a Word Document then it could be easy-
IF.... the Filenames of the images on the CD (the chosen list) are the same as Filenames in your Catalog, then there is a method to search and select all the chosen files.
Read all the Forum Thread at- LIGHTROOM - Filter to a list of images by using multiple file names at once | Photoshop Family Customer Community
You will read that one "catch" to the process is that Lr search does not like spaces in filenames, and this will upset the method.