Thank you. That error message in fact started appearing after I did some more experimentation with the META tags. (Added a Photo Card to see what happens). So, that solves the mystery. Thank you. I will probably have to write a small proxy. How does twitter treat a REDIRECT while fetching cards? What I mean is say I put in a server api
/proxy?url=‘ENCODED_IMAGE_URL_GROM_GOOGLE_MAPS’
and this API just does a redirect, will the twitter robot still come to play?
The same url endpoint works fine for facebook & G+. Probably because it fetches the image from browser and not from a server BOT?