You may know this by now, and it may not have been possible back then, but there are two things you need to check to see the actual map in place, rather than just a friendly external link:
- whitelist openstreetmap in settings → security
- if necessary, ensure the iframe includes the https flavour of links (you may have to manually add the ‘s’ to ‘http’ - check both links, the one inside the iframe tag may be just ‘http’).
Then the map should appear as expected:
View Larger Map