The EDM has an entry with a colon (":") as part of the account number
This value is not matching. Can a colon be used as a separator in the entry field?
Do not use a colon as the data will not index correctly. The colon ( : ) is a special character that is used as a token separator and should not be used as a part of the data set.
NOTE: DLP version 12.5 onwards multi token matchin feature has introduced. Using this feature DLP is able to index cells having colone in string as well as it performs detection. Screen shot of such detection is given below where header value having colone in it being detected.