I think your thread may have gotten lost in the "new poster hold", so I will get the ball rolling here.
I start by saying your real-life observations are all common things to see with dyslexia, and had me (with a dyslexic DD) nodding familiarly all the way through. Until the final line with the pseudo-word and spelling scores, which were surprisingly high. Still noticeably lower than general verbal ability though. I will leave it to our resident expert aeh to pronounce how seriously to take those scores, given what you see. I will note a couple of considerations though, before you draw any final conclusions on dyslexia.
First, do you have any scores that directly measure phonological processing (say from a test called the CTOPP, but there are others)? These dig a little deeper than pseudo-words and spelling, and are that much harder for a verbally-strong kid to fake. From the scores you've reported, your child does seem to struggle a little more when more context is removed (scores drop from general reading comprehension to individual words to pseudo-words). It would be worth knowing if that pattern continued with direct measures of phonological skills (may be called blending and ellison). Your DS does have nice consistently high scores overall, including in working memory and processing speed. These (especially WM) are often lower in kids with dyslexia, suggesting your DS may have stronger compensatory mechanisms to draw on than some kids. (This is good in the long run, but makes it a lot easier to hide struggles when younger).
Second, the auditory processing issue is important to follow up on, as deficits there can cause challenges with reading that look like dyslexia (if the brain is not interpreting sounds properly/ consistently, it's really hard for it to make the right connections between sounds heard and symbols seen on the page). In other words, even if the testing does show phonological weakness, the cause could be auditory processing rather than dyslexia (or it can be both).
Finally, the good news: regardless of cause/ diagnosis, your son clearly has a reading a weakness, and you are absolutely right that its impacts are about to escalate. OK, that's not the good part, sorry. The good part is that regardless of cause, a quality phonological-based reading program can help him. Our saving grace was a home-based program called "All About Reading" (
https://www.allaboutlearningpress.com/all-about-reading/). Your son may be a bit old for it and be annoyed by its cuteness, but it was amazing for us (we used in grade 3 and skipped the cut and paste activities, just doing the actual reading exercises embedded in them). There are other programs like "Toe-to-Toe" which may work better for an older kid, and others here can speak to.
The "relative weakness" thing can be crazy-making when you have a 2E kid. Many psychs are extremely reluctant to diagnose an LD unless key scores are below an absolute threshold (usually 12th percentile), regardless of how out-of-whack those scores are with the rest of the kid. Even psychs really experienced with 2E have told me "the DSM-V no longer allows for a 2E diagnosis". Argh! The best advice I can give is to trust your own observations here, and address the challenges you clearly see, regardless of whether or not the psych is willing to label them. And if the label is important to accessing supports or services, do keep pushing the psych to make full use of all the data you've gathered, together with their own observations and clinical judgment (and not just focus on the test scores). In a pinch, you can also take your results and seek an second opinion from someone with significant 2E experience.
