RHEL 7 isn't a supported OS. The VMgr is a piece of Polycom software wrapped in WAS so even though WAS would work there's no saying that Polycom's stuff will. I suggest you reinstall the OS and start again.
I install all the Sametime stuff on CentOS in my labs but always adhere to the versions in line with RHEL and it works fine.
http://www-969.ibm.com/software/reports/compatibility/clarity-reports/report/html/softwareReqsForProduct?deliverableId=2EA10FC0524011E5AAAA084C1D9D5D44&osPlatforms=AIX|IBM%20i|Linux|Mac%20OS|Mobile%20OS|Windows&duComponentIds=D015|D016|S003|S007|S009|S012|S010|S008|S011|S002|S005|S006|S001|S004|M013|M014&mandatoryCapIds=30|9|13|25|20|26&optionalCapIds=7
Take a look at the SystemOut.logs from the deployment manager and STConsoleServer directories. If the VMgr is trying to use a username/password and it is failing to authenticate with either of these servers then you should see an exception in those SystemOut.logs. You may have provided the wrong password in the deployment plan or another reason....