Hi Victor,
Greetings from Syncfusion.
We suggest you to use the below code to assign the datasource to the scheduler for the same we have prepared the below sample for your reference.
let scheduleObj = document.querySelector('.e-schedule').ej2_instances[0];
scheduleObj.eventSettings.dataSource = data;
Kindly use the above suggested way and let us know, if it resolves your problem and also, if you need any further assistance on this.
Regards,
M.Vinitha devi.