My wife inadvertently put diesel into her petrol Forester & drove until car quit on 2013 Subaru Forester

All necessary work, flushing of fuel system & injectors, was carried out by our local Subaru dealer and car runs fine, but they can't clarify if the catalytic converters have been damaged and whether one or both converters need to be replaced. After getting the vehicle running there was a sound of loose metal bits coming from in and around the exhaust system and the dealer claims to have retrieved small metal fragments from the front catalytic converter. Subaru dealer claims they've not had this type of issue on current MY13 model and cannot advise further until a similar incident occurs elsewhere? Any insight / guidance is welcome.

Asked by for the 2013 Subaru Forester
Art this point all you really should do is wait and see if the onboard computer turns on the check engine light and sets a catalyst efficiency code or not. It's not a warrantable situation now, so make the car decide if/when the convetors need replaced.
1 more answer
right off the bat it sounds like an expensive fix, all the dealer needs to do is pull up the front and rear oxygen sensor pids and compare after vehicle is warmed up. the front sensors should be switching or have a wave pattern if graphed and the downstreams should be fixed.