Yeah not just Ghost typed Confuse Ray, it also has Water Pulse which, as you saw, can also confuse AND hit Absol's not-exactly-stellar defenses while doing it. Bringing an Absol against a Starmie is basically betting on being able to dodge its traps and OHKO it before it gets you stuck wasting turns with status effects and whittles you down anyway.

But Erika's extremely specific weakness to Scizor in particular almost feels intentional. You bring in a fire type, Tangela trips you up with Ancient Power. But if you went and caught the crown jewel Scyther out of the bug catching contest and evolved it, congratulations, you found the one weapon that Erika's entire team seems almost intentionally set up to lose to. If she had a single fire move anywhere it'd be an expert level trap.