Looking at his profile and judging by his pattern and ranges of scores I would say no. His verbal skills are average and similarities, which is the task heaviest on verbal reasoning, is not super strong. His scores indicate that he will probably have strong math skills if the pattern remains the same. Kindergarten thought 2nd grade are so verbally slanted. I might do kindergarten, see how it goes and consider a first grade skip if it seems necessary.
Sally, you may have missed the note below the scores that the Similarities score in particular was "suppressed" by his giving overly complex answers that didn't fit the scoring manual. Some specific examples were included in the report but I'm not sure they should be posted here as they mention some of the test content, but needless to say, nothing on the WPPSI is looking for answers such as "proteins and fats" or "hydrogen".
His verbal scores were noted to be lower than his likely ability because when asked to list whatever it was he was supposed to list in 60 seconds, he listed like 5 things, said "And that's it", and then had like 55 seconds to spare. The reviewer also noted that "he answered incorrectly on purpose during the Early Reading Skills subtest." His phonological processing scores on the NEPSY-II were at 75%.
This is kind of the part where I'm finding this whole testing business vastly unhelpful because it seems like every single thing on the test has a caveat attached. I sort of want to go back in time and have a do-over or a test that isn't 2 hours long.