The initial plan was to breed Lwazi with both females; and there was still hope Evelyn would conceive following the birth of Marion's cubs last year but obviously this hasn't worked out for some reason or another and she's been given another shot with Baako at Mogo.
Although Lazarus's line is well represented, Maya's line is only currently represented through Baako at the moment (although one of his younger brothers, Sheru is currently in a breeding situation at Werribee). It's unlikely Maya will breed again, so with most of her offspring in non breeding situations, I'd imagine there would've been a strong desire to make the most of Baako.
Evelyn was photographed last year with prominent teats, which made me wonder if she was then heavily pregnant or had just given birth. I’m wondering if she had an unsuccessful litter as there’s otherwise no discerning reason why she shouldn’t have conceived. The initial recommendation could have then changed after they were assured Marion would have female offspring to build up the Dubbo pride.
Maya additionally has her five cubs at Taronga, but it wouldn’t surprise me if those cubs (especially the females) remained at Taronga long term in a non breeding pride. Maya is heading towards being post-reproductive and they’re a cohesive pride that are well suited to the exhibit when they’re not trying to escape it.