Insert Image and CL

Is there a way to code a text box input as readonly: true or something like this? I am using the text box as a way for students to upload their work. However adding this to my slide now prevents me from seeing the checkmark on the teacher dashboard. Any assistance would be greatly appreciated.

Checkmarks are not possible with text inputs or explain prompts.

Could you give them a math input (with correctness for you) where they put their final answer and a text input for their work upload image?