There's an episode of Blackadder where Edmund meets Liz One, and fails to prove that he is a sorcerer by showing her a futuristic rewards points credit-card form the super market chain Tescos.
Morality = A spectrum of behaviour.
Altruism = Doing good for no pay.
Yup.
The end of the episode had a whole bunch of aliens who figured out that they had been lied to and swindled, finally catch up to the Think Tank and try to kill them, because the Think Tank are bad people.
The Tank were tricky trickers tricking the tricked.
If the Think tank had truly met the Vidiians "recently" then the Think Tank had a Star Drive that could get Voyager Home in the same time as it took the Think Tank to get from Vidiian space class to the Caretakers Array to where they were this episode in Season Five.
Granny from the Beverly Hillbillies invented the cure to the common cold decades before she moved to California, and was amazed that Mr Drysdale didn't know, because there was a full page article all about in the Hooterville gazette.
Good lies are unverifiable lies.
No, what I mean is that the Tank were good enough to only list their real accomplishments, without having to make up fake ones. Lying about curing the Vidiians seems pretty useless at this point. That's also a reason why I believe they're truthful, because they had nothing to gain by lying about it. What if Janeway had said "I don't believe you. Prove that you've really cured the phage."
Why risk that? If their objective was to convince Seven to come with them then just as I said they would have known or guessed about her dislike for lies and deceit.