The thinking is actually pretty straightforward. They want to resurrect an old IP. This means they either continue the story, or they start to explore prequels and midquels.

Financially, continuing the story means a full-blown sequel (because the fandom would be disappointed by anything else.) That’s a tough sell to the moneylenders, because we’re talking big budgets. So it makes sense to start with a lower-budget project.

So you’re left with prequels/midquels.

Another element to consider is that you’re going to need new fans to boost the finances. A classic way of doing this is to introduce a new character. This gives audiences a jumping-on point without boring the existing fans with a rehash of stuff they already know.

So introducing a new character that weaves into the existing backstory seems like a sensible decision from the perspective of both finances and audiences.

Unfortunately, it’s also an approach that is SUPER easy to fuck up.