I've seen at least one domain offered in domain marketplace on DP - where this problem was paramount. In fact, the trust flow was in fact - zero! Well, anyway, it would be good practice to examine domain authority (DA) in conjunction with other metrics to make sure a domain is worth buying and/or working with.
DA depends on a domains age. So, do the math it may have TF low or zero but DA could say a different story. And before buying it many things have to consider not just these things.
Age has nothing to do with DA.... usually high DA + 0 TF = SPAM/low quality backlinks, probably in high volume. when buying a domain you'll have to check the BL profile manually, there's no other way around it. But DA and TF can be good for initial filtering, and this does not look good...
It does sort of make that metric look bad. I mean, it seems to be sort of a fraud (DA). Actually, perhaps trust flow or another metric should be looked at alone - and not in combo with DA.