The image submissions in my survey are listed as attachments, with no association to the questions they were submitted in.
Image attachments use keyword properties to associate an image with the question for which it was submitted. Keyword properties are not supported by ArcGIS Enterprise prior to 10.8.1, so an image submitted to a survey published in an ArcGIS Enterprise portal prior to 10.8.1 will not be associated with a question. Similarly, images attached to a feature through a method other than a survey (for example, in ArcGIS Pro or an ArcGIS Online web map) may not have keywords. To learn how to automate the workflow for updating attachment keywords, see Update attachment keywords.
This can happen if your template uses a font that isn't recognized by the PDF report engine. You can fix this by embedding your required fonts into your DOCX report template.
Report generation will automatically fail if it takes too long to complete; the exact timeout limit can vary depending on the complexity of the data, up to a maximum of 2 hours. This lengthy generation time can have multiple potential causes, including many maps or a large number of images. To avoid this, consider truncating your reports or dividing them into several smaller reports. If a report fails, credits will not be consumed.