Pushing the sylink.xml shouldn't take more than a day.
I did 17,000 systems off my laptop at a clients site running about 10 scripts in paralell and it all worked flawlessly
If you used the same password as the encryption key and SQL DB in the next step you can find it out by adding an addtional SEPM.
During the install process you choose to add a server to an existing site, then it will ask you for SQL credentials.
I tend to use the same one all the way through the install process, but not sure it will help you out.
good luck
Z