Probably not, but if you have the TMG admins, they should be able to configure it based off of whats needed for ISA2006
Check out this link (especially the comments):
http://www.shudnow.net/2008/06/24/publishing-symantec-enterprise-vault-in-isa-2006/
But really after all, /EnterpriseVault is just a website, it should not be out of the realm of capabilities that your ISA/TMG admins should already have
https://www.linkedin.com/in/alex-allen-turl-07370146