It hardly takes any coincidence at all to convince her.
She inherited her grandmother's sword three years ago, at sixteen, and has taken good care of it since. She's going to college over in Hobbs, but she's home for the summer, so when she hears about the dunj – well, she's here, and there's only so many magic weapons in a town this size, so it might as well be her.
And, the more she considers the idea, the more she finds herself warming to it.
She packs a sensible gear kit: water, trail mix, energy bars, Gatorade, first aid kit, spare charger pack for her phone, multitool, (mundane) gun, change of clothes in a waterproof bag, sunscreen, bug spray, Sterno, bedroll, emergency flare. She swears up and down to her parents that she'll call for backup right away if she gets into more trouble than she can handle.
She takes her car as far as the terrain allows, but eventually she has to stop and go on foot.
She sets off into the desert, pack on her back, sword on her hip.