I know nothing about heat treating, but Buck uses 420HC, S30V, BG42, ATS34, CPM154, S90V, S35VN, D2, and numerous others. They seem skilled at adapting their process.
From what I've read Bos overseen the setup and everything heat treat at the facility overseas, and I assume Buck has reliable process and quality control in the overseas plant(s). Besides; Paul Bos has been retired for years as I understand it, and it's more or less his technique and not him personally overseeing the process.
While there are a lot of bushcraft capable blades from Buck, the Hood knives come to mind first, along with the Compadre, and a few others; I'll agree that they're lacking a true, flat ground, carbon steel, 1/4" thick knife that's bushcraft specific.
I'd like to see Buck concentrate on their pedigree knives: 100 series fixed blades, 110/112, and the 300 series with more "in-house" enthusiasm and not count on the easy buck from wholesalers to come up with new knives in those collections.
When I can buy a D2, drop point, 1095, G10, Damascus, flat grind, aluminum frame, etc, etc..110 for little more than a standard 110 or significantly less than a custom shop knife, the only winner is the consumer. Buck is perhaps leaving a ton of money on the table with these exclusives that could go to new product development, more options, etc. The "easy money" plan is a short term fix that can devalue the brand in the short term and sour brand loyalists in the long term.
That's my $0.02...