Well hopefully it’s already the case that if someone intentionally sabotages another participant, and can be proven, they will receive a penalty worse than permanent disqualification.
So now rather than just testing the winner's skis, you need to track and monitor everyone's skis to prevent tampering?
No, random sampling can be done, although obviously not foolproof would still be better than nothing. It’s a common practice in most other industries, organizations, and even in sporting organizations with drug usage, etc.