You are nearly there, wampmanager.ini is recreated every time you run wamp. What you actually need is an uncorrupted wampmanager.tpl.
If you have a backup, replace the wampmanager.tpl
file in \wamp
SECOND ANSWER:
You could try this.
Rename the old wamp folder.
Install WAMP again, using the same version of wamp Apache,MySQL.
Copy your database's from old location to new location + any website code.
That should get you back to where you were roughly.