Hi,
From the information supplied it would appear that you are both the employer and the employee. An employer should be asking for receipts in relation to expenses and if this is the relationship you would be acting under then, yes, as the 'employer' is reimbursing the expenses, these would need to be reported within the company accounts. You can see guidance here:
Expenses and benefits: cash sum payments to employees
As long as your employee has actually spent the scale rate payment on business expenses, you will not need to check every single receipt, it is fine to just check a sample.
You can see further guidance here:
EIM05210 - Employment income: scale rate expenses payments: subsistence expenses: sampling guidance
If you have further specific questions relating to this enquiry you should write to the following address, quoting the PAYE reference number:
PT Operations North East England,
HM Revenue and Customs,
BX9 1BX
Thank you.