I'm thinking that the preservative treatment would be more on the line of Thompson's Water Seal - or something like that. Big difference than putting lumber in a big ole' tank and actually 'pressurizing' the whole mess to force the chemicals into the wood.
As far as them not sealing the open cut - well that just makes me think it's just another shortcut. Could also be an oversight on that one particular vessel - kinda' doubt it though.
All the lumber in my ole' 1988 Bay was nothing more than 5 or 6 ply. Just Home Depot junk in my opinion. Probably spent more money replacing with Okume than the whole boat cost to originally manufacture

. Small joke there

.
Gotta' remember that during those years Bayliner had a bad rap for using inferior products and shoddy worksmanship to produce a pop out boat. For all of the 20 plus year old Bayliners there will always be an issue with that problem. But, when I bought mine it was the boat I wanted so I just sucked it up and made up my mind to restore it correctly. Which by the way is still 'under construction'.