Dr Bottomley is the only in-game character discovered so far who is NOT a dev alias or a character from the original HL
A possible candidate for Paul Bottomley was found amongst Stormseeker's Steam friends, going by the username 'Gruntfuttock'
Also - recently added on Gruntfuttock's profile (after we initially checked him out) "Lately I have been shot in the head by HECU in Black Mesa. As far as they know."
There is the idea is that his name is clue D as a method for solving the VIC cipher, giving us the letters needed for the straddle checkerboard: D- RBOTMLEY - possibly wrong since we now know he's an IRL friend of Stormseeker
"I'm Paul Bottomley (for my sins in a past life, no doubt), a friend of Chris's, and was once shot in the head for science. I was planning to create some kind of short story about how "I" survived the BM incident through the clever use of cloning. It wouldn't have been related in any meaningful way to Stormseekers magnum opus.
But frankly, I'm just too tired. And it probably would detract somewhat from what Stormseeker has created for everyone - about which, I hasten to add, I know as much (less than, in fact) as anyone here. So, yeah, let it be known that Bottomley is alive and continuing his very ethical and worthy research in a major American City."
Shortly after posting, this was censored by Stormseeker to remove the words "cloning - magnum opus - American City"
From this we can infer that at least one of the other scientists survived the HECU assault (perhaps in name alone) by cloning themselves. Whether the cloning facility was at Black Mesa itself is uncertain.