Firing you because they found out you went to an interview sounds borderline illegal to me, but I'll guess you have checked into that. (I live in the UK - maybe in the US thats OK).

If you are asking me I would hold out for a job at least vaguely in the right field SQL/Network admin or maybe some of both at a small company. Even with an MIS degree, you will be hunting around for entry level IT jobs again. If you can get one without it, who needs it?

I would concentrate on leveraging your existing, proven skills in network admin to find a job using some netwrok admin and some SQL. Getting a db developer job on study alone may be harderr