Is there no option for her to address her debt problem rather than simply walk away and foist it on her ex-partner?
Forgive the language, it is difficult to have much sympathy for your partner, by walking away and forcing her partner to deal with her outstanding debt she has put them in an untenable position, which is probably the reason that they are threatening to expose her.
The banks can attempt to pursue her but they are unlikely to at the moment. Obviously chasing her will be more difficult for the banks than chasing her partner still in Ireland. In all likelihood that person is currently under severe strain due to being chased by the creditors. If, however, the ex decides to bankrupt themselves (and that may be the only option open because they have been abandoned to carry the full burden of the debt and deal with the creditors) then she would probably become fully liable for the whole debt (depends on the contract but generally it is jointly and severally liable) and the bank may then decide it is worth their while to chase her down if there is a chance that she has an income to repay it, despite her being in another jurisdiction.