Hi. Looking at your picture, the white thing can simply be a collection of dry and dead cells in the ear canal. Assuming that there is no ear discharge and pain since you haven't mentioned anything about it, I would ask you not to worry much. But the ear definitely needs an otoscopic evaluation.
Next Steps
Do not wait for your surgeon to return and get an ENT consultation as soon as possible. A simple otoscopic examination can very well diagnose what that white patch is.
Health Tips
Never ever probe your ear with buds, especially after undergoing an ear surgery. It can lead to graft infection/ failure and recurrent ear infections.
Good day.