Send the notice to the HS athletic directors, and tell them if an accident happens in the pole vault, and the family sues the school district, and it's shown that training opportunities were made available to coaches, which those coaches chose to "pass on", then the floodgates are wide open liability-wise.
Not to say that any single clinic is THE clinic to attend, but point out that if the coaches choose to not go to ANY that discuss pole vault safety, they're leaving themselves wide open. ADs and administrators understand liability and financial risk better than helmets, landing pads and the like, and might respond faster when you talk liability exposure. Another possible avenue- Approach the insurance companies that offer comprehensive policies to HS and college athletic programs. Explain what safety training programs are available (it would help if they carried a "USATF-certified seal of approval"). See if they would offer a 'training discount' to schools whose coaches get 'safety-certified' in their sport. Kind of like a good-student-grades discount to young drivers on automobile policies. Of course you might have to show some statistics that programs whose coaches get this kind of training have a demonstrable lower claim rate. If any insurance companies agree, then that becomes another selling point to AD's and coaches to get to those clinics or training classes- they benefit immediately via lower policy premiums. By the way, the "approach the insurance companies" suggestion is maybe something that USATF should take up. RT