1) Thanks for posting your system specs
2) Is this question serious? Are you calling in the US? And do you have a Very Good Lawyer? (I strongly suggest you keep the front door of your call center locked and have an employee "having a cigarette" outside of it who knows the secret knock to let you know when the FCC truck arrives with the "team" to take all your computer equipment ...).
3) That being said (yes, what you are asking is unquestionably illegal, and if you get caught my description actually will become a reality, no joke, been there, seen it!): But the ability to set the callerid on each call to a different number is not related to the "callerid" field, but to the "Custom CallerID" field directly below it if your version has this. You can set the callerid based on area code OR in a special field (if you want more precise instructions ... try the Vicidial Manager's Manual or at least press the "?" next to the Custom CallerID field).
4) Do not try to call us from jail, we don't do bail.