I think if you can afford the clinic cost - then send him. If not, I wouldn’t stress about it either.
We coach a bunch of young kids, some from a private school and some from fairly low SES backgrounds - and everything in between.
If ever the kids come to us and ask about going on a course - if it isn’t a financial decision we say yes pretty much every time. Spending time with other like minded kids, learning new skills etc can only benefit their development within the sport. As a kid I loved going away on coaching clinics and the kids we coach seem to take so much away with them, there’s always something for them to learn.
The way triathlon is going (infact it’s already gone!) the top athletes train as triathletes from very young now, they become experts at tri specific skills like transitioning, tactics, etc. Just listen to Macca’s comments about how fast the ITU guys are transitioning now - they’re the sort of skills these kids are being taught young and that’s where you want your boy if he wants to race. **That’s if HE wants this as well as you - I’m sure you’re not one of ‘those’ parents 
Again - that’s if the $$ aren’t an issue which it’s sounding like is your situation.
That said - if it is a financial decision, then there’s enough knowledge on here to be confident that your son is in good hands if you ask the right people.
The trick with the kids is ‘selling it’ to them, getting them captured and keeping them interested. The kids we coach whose parents are also involved in the sport tend to stick around longer and get to see the gains from training which is generally the carrot. The fact you’re asking these qu’s about your kid suggests he’s in good hands.
My wife wrote a really nice piece for a local magazine on nurturing young talent a couple of months ago, it doesn’t really answer your question…but you might like to read it regardless…
"An athlete recently quizzed me on my style of coaching – and I compared his development to that of a juvenile olive tree - It was one of those ‘off the cuff’ remarks!
The more I reflected on it though the more I realized the development of talent is in fact very similar to the growth of juvenile trees.
In my metaphor I used the example of the young trees we plant up here in Northland, we’re on a windy coastal block with seasonal extremes of wet and dry.
I get a lot of emails from keen parents searching for the next ‘edge’ for their child to get ahead of the crowd. Every time my reply is simple – get them to contact me personally and they can tell me all about themselves.
We’re new to country life – and I’m sure the neighbors still look on us as ‘townies’. But we’ve noticed in that short space of time that our trees need room to move. We stake them for the wind – good support is pivotal in those early years just like talent needs the support of parents, mentors, coaches and friends. But tie the trees too tight and water them in the dry summer months, and you’re setting them up for failure.
If the young olive doesn’t learn to move in the wind, bounce back after a storm and steady itself for the next season – it’s unlikely to develop into a mature fruiting tree. Likewise the young athlete that has no say in her direction, who never experienced adversity and is suffocated with support, will struggle when the winds of life come blowing.
A tree looks great in summer if watered and fertilized, lush green leaves and fast growth will ensue. However take that water away as mother nature invariably will at some point - and the shallow fibrous roots you’ve encouraged will soon dry out. Leave it dry and deep ground roots will eventually find a moist spot.
As a child I had to make my father a coffee at 5.45am – that was the deal. If I wanted him to drive me to swimming there was first a price!
Far too often I hear stories of ‘high performance’ being about what toys you’ve got, an Iphone for logging training, a power meter or heart rate monitor. These tools will never replace desire, resilience, and a commitment to being the absolute best you can be.
Hamish Carter has slept in the transition area of ITU World Cups on more than one occasion, and when he’d finally clawed his way to the top of the sport he was good enough to let this developing athlete and others sleep on his hotel floor from time to time whilst attempting to follow in his footsteps.
I love helping athletes chase their goals. There’s nothing more exciting than someone coming to me who truly wants to win - and nothing more rewarding than working together toward achieving just that. Ultimately though – there’s only one person who can take ownership of those goals – some people will tell you not to sweat the small stuff but in my mind it’s your responsibility to sweat every little detail if you’re serious about chasing dreams."
All the best for you and your Boy.