Great ideas above.
However, personally I'd rephrase that as he won't see a counselor... yet. I'd accept that for now and validate his concerns about talking to a stranger, while also providing him with feedback that the option is open, and when he feels the time is right, he could help pick a counselor which seems like a comfortable "fit".
Meanwhile, might a
book be of help... if he reads and sees himself in some of scenarios (but not others), possibly he may begin to discuss this with you, giving you the opportunity to help where you can (and suggest an expert where you cannot).
My guess (and this is just a guess) is that he is compensating for something, and unable to keep compensating well and at the same time keep up with the barrage of new information and stimulus around him in the school setting.
Kids can max out their ability to compensate around this age. It is not their fault (it is just a matter of the brain they were born with) and they may need to learn new tips and strategies for making the brain work for them in various situations.
Has he been tested for 2e and/or have you had reason to suspect there may be a second exceptionality? If you are uncertain what to look for, there are checklists to peruse.
