Well, that last bit is not at all what he intended to say and that people may get your interpretation out of it is exactly why it is a wrong answer: it's an answer likely to be wrongly understood.
You have to wonder why he mentions 'karma' in the first place. And the best explanation for mentioning it is that he truly believes that those who give trust will receive trust.
Note that this does not imply the converse: it doesn't mean people who do not give trust are not to be trusted. It's just his personal belief that it's good to trust 'the (people in the) system' and the problem is that his personal belief does entirely align with the message he wants to get across, at least not in the eyes of people who do not believe in karma.