Alright!
Cat, move to the edge where Derbie is and draw the Rothé there!

Ashley!
We're moving onto the green arc, the Rothé is too far away to attack us now if we leave the cart! I'm too far away to use my spells from here and you need to stay within 30ft of Cat to assist her. We will help each other up that wall onto the green arc. We'll be even safer from the Rothé up there than where we are now.

gets down from the cart and attempts to climb the wall with Ashley's help, then uses dash north towards cat, staying clear from the edge of the green arc