I do not advise this for everyone but I personally would let Glyph install the directories and then stop Glyph after a few moments. Next I'd put the old game files in the newly installed directories. This could absolutely cause problems but most installers and launchers these days perform an integrity check on the directories/files before launching. In short, the launchers automatically update, patch, or replace, etc... Anything out of date or incorrectly sized gets the boot if it doesn't match a byte check. This method might transfer some unnecessary bloat on your drives but it might provide quicker access to the game.
I actually did this with ArcheAge (Gamigo property utilizing the Glyph launcher) a number of times because it was something like a +99GB download then the decompression process took ages. Download servers were always swamped at launch so no matter how fast or low latency my connection, bandwidth was limited on their end. Then there was the wait for decompression, I have no idea what sort of inferior decompression scheme they were using but a cutting edge PC with SSD and/or NVME drives and it took over an hour or so.
There's really no reason to do this with Fractured, the game isn't an incredibly large download.. but I know some folks still have bandwidth limitations.