I see the refferer and your comments, so I scampered off to google to play in the console.
I had already verified te site through ISP verification.
I had enabled a couple of map APIs , not sure which one you want, GEOcode I assume.
Then I put in the exaxt url they had in the error as my allowd site.
Now I atleast get the OOPS page instead of a blank,
Let me see if I can get the right config now.