Hi Jeremie,
Thank you for contacting Syncfusion support.
In Scheduler, currently PDF/ICS Exporting functionality is achieved by referring the required exporting related assemblies (which contains classes for export functionalities). Since it is not possible to make use of those assembly references in PHP application, currently there is no options to achieve it. Also, we have created the pure wrapper classes for all our controls in PHP platform which will be available in our upcoming Volume 3, 2016 main release (It doesn’t include export option in this initial release). In JS sample, PDF export functionality is achieved by making use of service hosted link. Kindly visit the below link to know more about PDF export in JS.
Regards,
Karthigeyan