I think it’s because Hades wasn’t really playing her in the sense that he didn’t love her; he just wanted it all–the girl and the power. When TLK was started to work in Skin Deep, Rumple still loved his dagger and his power; but there was enough under that (his love of Bae, for example) that overrode his desire to hold on to his power. At least that’s my guess. Until Hades got to SB, his love for Zelena and his desire to have a family was at the forefront. But once he got to SB and he realized that with a beating heart and the heroes left behind, he could once again take power, that’s what drove him.
That isn’t how it appeared to me. Hades flat out told Zelena back in 5×19 that he wanted to trap the heroes in UW. He also brought along his “family heirloom” (aka the cheap, glowing toy thunder bolt) from the UW to SB. So, it seems clear to me that Hades didn’t *just* want to be a family with Zelena and baby Robin. It seems like he really wanted to rule SB all along.
"That’s how you know you’ve really got a home. When you leave it, there’s this feeling that you can’t shake. You just miss it." Neal Cassidy