The Moff didn't need the baby, he didn't need Grogue, he had something better, a Padawan. A real one, one from the jedi temple before it was destroyed. The kid was strong too. If only the child would listen to him, hear him out. If only the child understood what he wanted. It wasn't for a selfish reason, well, not to him. It was for the Galaxies greater good. With a padawan at his side, a Sith padawan, he would be able to rule the galaxy with an iron hold, no one would be able to question his rule.