The common mechanism I've seen is, 'if you contribute $X to our employee PAC the company will donate $X to one of these nonprofits.' And of course free booze at functions. Tucking compensation into bonuses is clearly way out of bounds.
I don't think any of Trump's cronies will be prosecuted (effectively) while he's in office. When Trump's out, I ardently hope they hunt them all down. But politics and politicians being a giant circle jerk, I have my misgivings that it's ever going to happen.