Obviously you don't know enough to say Canhelp is incorrect. The fact is when an injured worker cannot schedule their therapy before or after work-hours, they can attend therapy during work hours. Surely in the OP's case, her employer has accepted her claim which means if their Network of Doctors schedule appointments for therapy during work hours because there is no space otherwise, the employer wouldn't object.
If such workers comp. claim is denied and the injured worker gets fired for leaving work to go to treatment, there would be penalties under Section 132(a) of the California Labor Code. I don't think any employer would want to face a "Serious and Willful" action on top of a Workers Compensation claim by refusing or retaliating against an injured worker who was forced to go to therapy treatments during work hours.
Glad I could educate you, Cyjeff, on California Workers Compensation Law.