Sorry to hear about that :(
Sketches have been discussed and are allowed as long as they represent the organism that was observed rather than being based on field guide images etc. If you want to, you can add the observation field “Illustration”.
If you add observations with no photo or sketch, there is no need to hide or set to Private. Such observations won’t appear by default in Identify unless an identifier changes their filters to specifically look for them. You can make as many observations without photos as you want without any problems.