Not impossible, but I think in this case highly unlikely. The picture that is also from UCB Bot. Gardens, but not posted by you, shows the plant with yellowing leaves - I assume that even if it is not the exact same plant that at least it is a sibling grown under similar conditions. The yellowing is usually a response to too much sun, A. guadalajarana loves the sun, A. bovicornuta and cousins do less so and show that kind of typical yellowing when distressed. Maybe it is an A. guadalajarana x bovicornuta hybrid? It is hard to argue against a label put on in a botanical garden, but experience tells me that even they get it wrong on occasion.
