No, your reconstruction is incorrect, because "they are only to cover the cost of training and education" implies that it is the naturally advantaged who should pay for training and education!
Here's the explanation of the original sentence:
- Those who are naturally advantaged should not be rewarded simply because they are gifted.
- It is OK (e.g. for governments) to cover the cost of training and educating the naturally advantaged.
- It is also OK for the naturally gifted to benefit, but only if they use their talent to help the less fortunate.
To simplify it:
It's OK for them to benefit (in order) to cover the cost of (their) training and education.
It's OK for them to benefit for using their talents to help others. "for using" means "when they use."
It's OK for them to benefit to use their talents to help others. "to use" wouldn't work here.
Student or Learner