A 28-year-old woman from Delhi presents to the emergency department with acute-onset severe muscle pain, dark urine, and malaise following an intense 2-hour gym session in a non-air-conditioned facility during summer. Serum creatine kinase is 8,500 U/L (normal <200), myoglobin is markedly elevated, and urine dipstick is positive for blood but urinalysis shows no RBCs. Arterial blood gas reveals pH 7.28, HCO₃⁻ 16 mEq/L. Muscle biopsy shows normal glycogen content and normal enzyme histochemistry. Which glycolytic enzyme defect would MOST likely present with a similar acute rhabdomyolysis picture in a different clinical context?