The applicable charges would depend on exactly what each person did and importantly what evidence there is to prove it. As the exact conversations about what the money was for are likely only known to those two people it may not be possible to prove any crime took place with regard to the money she gave him. If he demanded money to keep it quiet that may fall in the realm of extortion/blackmail. If she voluntarily offered the money on the condition he falsely testify in her favor, that may be a bribery/witness tampering kind of offense.

