Some mistakes in the novels

This thread is for those who have read the novels. There are a couple of details I'd like to discuss.

In the UAKM novel, after Tex visits the Countess Renier's empty mansion and realises it was a setup, Tex reaches a phone terminal and leaves a message to Mac Malden that he should check it out.

Sometime later, after Tex is released from the police station, he decides to visit Mac, and repeats his request to investigate the mansion.

Now, it could be realistic to assume that his message was somehow "lost" in cyberspace for technical reasons and Tex has to repeat his request. I could buy that, but since we have to do with a piece of literature, there must be some "economy" for almost everything, such as some line of dialogue ("I sent you a message some days ago but you lost/forgot it? Well I wanted you to know that blah blah..."). There is no mention in the narrative that Tex's request is repeated, hinting that the author himself did not intent it so.

After all Mac's investigation turned out zip so the whole subplot doesn't serve any literary purpose, let alone to be requested at two separate points.

So did something escape proofreading, or am I missing a trivial subplot here?
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