Dr. Klein instinctively trusted them with more information than the average joe should have had, but I'm glad they've found out about Asabi.
I have a theory on why people trust Lois and Clark more than they probably should - and some other things.
We know that Superman/Clark has a strong bioelectric aura from his Kryptonian biology. But what if this aura also strengthens his psychic aura? As Superman, this psychic aura tells people 'I'm a good guy, trust me.' As Clark, it says 'I'm a good guy, trust me, I'm not different.'
This is purely on a subconscious level, but it means that Clark is telling people (on a purely subconscious level) that he's NOT SUPERMAN when he's not in the Suit.
Now that Lois and Clark have at least some powers, they both have 'Trust me' auras.