Are you OK to pay 30K if a better job comes up within a few months of joining?
A very simple solution. You advise your employer that you intend to pay the bond but due to the level of salary you are on you do not have $30,000 readily available. As a result you intend to offer a payment plan and will send them $1000 every month until the debt is paid.
If it ever got to debt recovery action or a magistrate you would be in a very strong position.