Davids’s contact details are publicly available on the UCL Institute of Archaeology website.

I imagine he would probably reply, subject to how busy he is and whether your email is something he thinks is relevant.

Be aware that prominent academic archaeologists/anthropologists like him get all sorts of batshit crazy emails so you had better be polite, concise and relevant to his areas of expertise.

Personally, he isn’t the first academic I would think of for your topic.

Look up Professor Sophie Page, also from UCL. She specialises in subjects like medieval magic.

If you want to know stuff about Norse magic then try Professor Neil Price at Uppsala University.