I should stress that this should be checked out with your local CAMHS, as policies can and do vary: however.
In our area, CAMHS can't prescribe unless a child or young person is also in some form of talking therapy. The waiting list for that is at least a year for the most urgent of cases - those where the C or YP seems likely to imminently attempt serious harm, or where they are losing touch with reality. Meds appointments are in theory easier to secure, because they are less time intensive, but again - can't offer meds without talking care, so the wait for the meds becomes just as long as they have to be done in tandem.
This policy isn't to be an arse. It's actually well-founded: it's because very depressed kids reach a point when the mood starts to improve when the apathy and lethargy of depression lift before the pain and distress do, and this can be really dangerous as the child still has the motive to really harm themselves, but now also has the executive function and energy to do so, which they probably didn't at their lowest.
If you can possibly, possibly afford it (and if this has gone on long enough, perhaps you could apply for DLA or PIP as clearly he needs much more care than the average kid this age, including through the night) a way around this might be to pay for counselling with someone who is properly qualified, properly supervised, and registered with a professional body - again, check with CAMHS in your area, but this might satisfy that requirement and you might get help sooner in the meds front, too. You can look for someone who is in private practice, but also works for CAMHS, in fact (I think using NHS staff in private practice is generally wiser - the NHS do check people out and have minimum standards, so it offers a bit more reassurance).
This has meant some kids with EHCPs, which fund emotional care that tick those boxes, have had meds care via CAMHS in reasonable timeframes.
I'm so sorry this is where you are. CAMHS has never been well funded, but right now it is in a truly terrible state. I feel for the staff working within it as well as the families affected. And the adult service isn't doing any better either.
No advice on what to do. I just send sympathy and solidarity. Too many families are in your situation.