I had a similar issue. I had to create a Universal Group and make it a member of the local admins group on all computers in the other domains. Then add my SCCM deployment service account to the Universal Group. Then I could deploy the client and use remote tools. I used a restricted groups policy to make the Universal Group a member of the local admins group on all computer in the other domains.
You can test this by logging in as your service account and and navigating to c$ on computer in the alternate domains. If you can then it should work, if not, maybe its a permission issue.