Can I update employee payroll records for gross and tax as a result of a colleague using the wrong payroll system in April?! Including RTI submission.... (on old system)

Hello StoneBaked, 

Is this there first pay run in Quickbooks, if it is, you can replicate the pay run for April, ensure you have the same employee id number in Quickbooks as what the employees had in Sage and ensure they are getting the same figures and don't submit the rti for April as it's already been submitted via Sage or you can set it up for May in Quickbooks entering the YTD Year to date) from Sage, still ensuring that you have the same employee id numbers.