Congrats on her scores! And I'm a school psych.
Was there any variation in the subtests? How were the WMI and PSI? (If done.) Did the bonus points (or lack thereof) for speed on block design affect her PRI? Even if not perfectionistic, a reflective kid can be unduly penalized for their lack of zip. Was a block design/no time bonus alternate subtest score calculated? If so, was it significantly different?
If the PRI is legit, another factor to consider is the extent to which abstract/fluid reasoning affects higher-level reading comprehension, especially inferential reasoning. The verbal subtests on the WISC include some verbal reasoning, but are heavily weighted toward crystallized intelligence. They also, with the exception of the Comprehension subtest, require relatively little receptive language, since Similarities and Vocabulary each consist of one- or two-word stimuli. Even Comprehension allows you to use your experiential knowledge and context to fill in language comprehension. And, of course, the questions aren't as long as multi-paragraph reading selections. Her language expression skills, by your report, are strong, and consistent with the VCI. It's the receptive language that seems a bit inconsistent with the VCI, but may be reflective of relative weaknesses in inferential thinking that potentially may be exhibited in the PRI.
I'm kind of pondering this as I go, so I apologize if there are gaps in coherence. But just some thoughts to begin with.
