I don’t think the Rest POST snap can perform a POST with a multipart/related content-type, so you might try the resumable API end point and see if that would work. I haven’t gotten OAuth to work on my Google Drive account, so haven’t actually tried this, but might be worth looking at.
It’ll require you to make two requests. The first will create the file metadata, which you could set the file’s title in, which responds with a location to upload the file contents. Then the next request uploads the file to the location that was returned in the first request.
