Will LQ need intel on the Diao over the long term? Yes, absolutely.
Does LQ need intel on the Diao right now to accomplish her short term and medium term goals? Not really. The Diao, as the Cai Clan's strongest supporters, are probably not going to go out of their way to mess with LQ, a Cai retainer, too much in the short term. If LQ gains enough political power to make the Diao feel uncomfortable about her non-peakabooness, they probably will. But that's a long term concern, so see above.
I think that building strong alliances alliances is probably the best way to deal with threats long term. And I also think that people are getting so hung up on the fact that the Diao don't like LQ that they're overlooking that, aside from the Cai (not to be underestimated, but there's still only three of them), LQ doesn't have any powerful ES allies. She just has a couple count clans who are kind of interested in her. I'd rather use the bonus here to work on making them more than just kind of interested.