Maybe I'm wrong, but I would assume that in the 1990s to 2000s studios were better about archiving production data, and there aren't likely to be "lost episodes" in this stash?
"Lost" is a relative term. I'd like to watch old episodes of MTV's "You Wrote It, You Watch It" (hosted by a young Jon Stewart!) but good luck finding that on the internet anywhere.
I don't know if MTV still offer this, but about 10 years ago they still had a service where you could get them to basically burn any show to a DVD for a small cost. I got a bunch of rare shows this way.
BBC famously lost their 9/11 coverage for a decade or so until they managed to find a copy they hadn’t takes over. Their policy is only six month retention.
What is most likely of value besides the teletext on there is the live stuff and any commercials.
you'd be not right. things happen. tapes get misplaced. tapes get lost. tapes get damaged. the people working at the studios are merely human. and at this point, there's even fewer humans working at the studios as they keep laying people off.