Remira let Sheva leave; there was no way around it. Even though injured and retaining a little bit of her strength, taking out someone like Sheva would still take time. This much she could assess depending on the danger she felt from Sheva.
Which made it easier for Remira to choose, focus on the powerful curse causing havoc at the back as for Sheva? Her smell can be followed up later.
There were few things that could be hidden from her nose, and as long as Sheva remained in this city, eventually, she would leave a trace that Remira could track. And it was then that she would get her answers, including what happened to the woman that saved her.
So she rushed, arriving at the place which turned her mute for a second.