Sorry about your situation.
First of all, you should understand that the photos are not "in" LR, they are on the Hard Drive in folders, so you do not have to "...get the photos from LR". LR is only a library catalog, similar to a card catalog in the local town library. It should be a simple matter of copying photos and the catalog from one drive to the other.
Here is what I would do: Assuming that all the photos are on his computer internal HD in a parent top level folder such as "My Pictures" and that they are a mix of jpg, raw, tif, etc. he should copy the parent folder including all the sub folders and photos to an External Hard Drive; this could be done outside of LR, either through Windows Explorer or Apple Finder. He should then also copy the LR Catalog from his computer to that EHD. With thousands of photos, this could take hours, but certainly not months. After you get that EHD, you then need to get LR on your computer if you don't already have it; use it to open the catalog on the EHD and then, assuming that the catalog may not find the photos, you need simply to proceed with reconnecting the "missing" photos.
If they are all jpg and/or tif files, only copies of the photo files to the EHD are necessary, which simplifies the whole process.
Perhaps others will present a different approach.
Joe's comments are right on. LightRoom doesn't touch the original photo file. It treats that as sacrosanct, like a negative. So putting all of the photos on a new hard drive is trivial. It's just a drag and drop operation.
You also want the catalog file. This is one big file that is made by lightroom. It contains all info that has been entered about the photos, including keywords (many of us use keyword tags on all our photos with names of people in them, so you can easily find all photos of Joe, or Mary), developing info (all the cropping and stuff that turns the original photo into a more finished product), etc. Again, copying this file is a simple drag and drop operation.
Once you've got all of this, you might want to find a local photographer with lightroom experience to help you organize and make sense of what you've got. It should be easy to find that person.
Another option is to simply export the photos from Lightroom. Impossible for this to take months. It should take 5-10 minutes in Lightroom to find all of the required photos, and then click Export. The files that are created can be placed on an external hard disk for you.
I'm not sure why Lightroom needs to be part of this conversation at all.
The images are files on a hard disk somewhere - as Joe suggests, just copy and paste them to a new location with the operating system.