If your code were correct you should get:

Test Passed: Value == "RE 13001:Gordon Road Atlanta/5"

in green color.

So that extra ':/' should be part of the solution then?

No, no extra ':/' at the end.
You could notice that now 9 more guys passed the Ruby translation.

143 guys passed the Ruby translation (see the top of the page) so I am quite sure there are no problems in the tests.

The 'instead got' statement is the output of my code.

So it's your code which appends something at the end of your "got".

The good result is RE 13222:Gordon St. Atlanta/2 and you returned ""RE 13222:Gordon St. Atlanta/2:/". You have a problem in your code. Cheers.