Figured it out, there was a system that had taken the same GUID as the SMS_Unique_Identifier0 for x64 Unknown Computer. Here is the query we used to track down the offending object. After deleting the offending computer all systems can see the available task sequences...
WQL Query (SCCM Console Query):
Select SMS_R_System.ResourceID, SMS_R_System.Name, SMS_R_System.SMSUniqueIdentifier
From SMS_R_System
Join SMS_R_UnknownSystem
On SMS_R_System.SMSUniqueIdentifier = SMS_R_UnknownSystem.SMSUniqueIdentifier
SQL Query:
SELECT
s.ResourceID,
s.Name0,
s.SMS_Unique_Identifier0
FROM
v_R_System s
JOIN
v_R_UnknownSystem us ON s.SMS_Unique_Identifier0 = us.SMS_Unique_Identifier0
I hope this helps anyone else that runs across this problem.
Matt