Facebook can add characters to string queries on posts. We have a workaround available to help get your redirects working properly.
There are two properties that help work around this issue:
Retain Query String: Controls whether query string parameters will be carried over to the From URL
Match Query String: Controls whether the redirect will require the query string to match
Important Notes:
If the Link To has a URL with a Query String, do not enable Retain Query String.
If a URL Does Not Have a Query String, enable Retain Query String.
Regardless of whether or not your URL has a Query String, always disable Match Query String.
The Query String is the ?Command=Something; for example, .aspx?AMID=112
Who can use this feature?
System Administrator | Owner
Instructions
Navigate to Modules and on the Site Tools tab, select Redirects
Select the Category your redirect is in
Locate your redirect and click Actions
Select Modify
Under Additional Details, disable Retain Query String and Match Query String
Note: If the Link To has a URL with a Query String, do not enable Retain Query String.
Select Save Changes at the top of the page
Add to Facebook as normal