If it's difficult to determine if the lending is fake, the alternative is to prove that the accounts involved are controlled by one person. That alone is enough reason to leave tags on them.
You cannot pretend to enter into transaction with your alts. That is an attempt to deceive the forum members.
Determining the difficulty of the fraudulence of a lending service is subjective, the difficulty relies on the intellect and competence of the creator of the scam, if they are dumb and incompetent then they will leave a trail of breadcrumbs that even the least aware would probably notice but if they are the dangerous one, which is the opposite of what I've mentioned then the degree of difficulty goes up but not impossible to the trained eye. Regarding using alts to fake transactions, I think that a determined and competent scammer would go to any lengths to do that.