Is there a way to insert a hyperlinked image into an InDesign data merge?

If you mean, can Datamerge place images dynamically ? The answer is yes. All you have to do is adding a "@" sign at the beginning of the field (ex: @logo ) Remember to preceed the @ with a single quote in Excel (like '@logo) in order to prevent Excel from interpreting the @ character as a formula.

Then the field has to host either relative or absolute paths. The latter seems to be more solid.

On the contrary if the question is : can datamerge place files and then set them as hyperlink to some url (possibly set in another field), the answer is no. You would need a script to do so or use a VDP plugin such as EasyCatalog which does this smoothly.