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Regardless of nominal classification, these are generally nice strong scores, with working memory the only low outlier. Whether he gave adequate effort, I can't say. He may or may not know himself.
In answer to your question: no, that is not statistically normal. But it's not necessarily pathological, either. You do report functional memory problems, so that suggests that this WMI result is more real than not. It's useful to understand that the WMI tasks are relatively rote in nature, and allow limited access to cognitive strategies. The skills involved are more akin to those involved in following multistep directions, and sustained attention for presentations of disconnected, decontextualized information.
His processing speed is very high, and may actually be contributing to the ambiguity about GT identification. Especially in the early grades, when the vast majority of academic skills are rote in nature, it is not unusual for speed of work completion to be confounded with speed of concept acquisition. This is a handy strength to have IRL, as he can be very efficient with already-learned skills. However, it is distinct from his actual rate of learning new skills, and especially abstract concepts.
I don't disagree with his grade placement, especially since he's obviously proven himself successful there. Actually, his profile is one which is (other than WMI) quite nicely suited to the kind of widespread academic advancement that schools are most likely to be able to offer. However, I suspect that his challenges with reading comprehension are not only because of overconfidence and careless responding. When you look at his abstract thinking (FRI), it's in the beginning of the High Average range, which would suggest that his inferential thinking may not be at the level of his basic reading skills. Decoding, after all, is more of a rote efficiency skill--which he is very, very good at. Keep in mind that, even if his FRI (which is probably the most closely related to mathematical ability) is only High Average, challenge and advancement in math instruction may still be appropriate for him.
As to his WJ scores, posting them is, of course, entirely up to you. They should be organized into up to four major skill areas: oral language (least likely to be reported), reading, written language, and mathematics. Within each area, there may be scores in a number of sub-areas: basic skills (e.g., reading decoding, computation, spelling/mechanics), applications/problem solving (comprehension, problem solving, written expression), and fluency (word or sentence level reading fluency, sentence writing fluency, math fact fluency). Each of these sub-areas can also be combined across subject areas to generate composites in academic skills, applications, and fluency. Sub-areas may also be composed of multiple tests. Yeah, it's a bit confusing!
I'd start by looking at the composites titled "Reading" or "Broad Reading", "Mathematics" or "Broad Mathematics", and "Written Language" or "Broad Written Language".
The next level down of interpretation would be (e.g., under Broad Reading): Basic Reading Skills, Reading Comprehension, Reading Fluency. Similar composite names for math and writing. You may or may not have all of these second-tier composites, as it depends on which subtests were administered.
