Deputy to myob, now payroll is broken

Hi everyone, a few months ago we attempted to link our Deputy to Myob to streamline payroll. However, the link up failed, and it appears that a duplication of items were created in myob. 

Now when we manually complete payrun, it has to be done in batches of employees of no more than 30 or so, otherwise myob fails. This can mean up to three separate pay runs each week to get around this error.

And because we failed the import once with these pay items, myob won't let us delete them from the file, as they are attached to a payrun (even though it was never completed).

Is there anyway to reverse this and cleanup our database and file, and try to link the two together again? Cheers!