R43 FORM & P45 - not relevant - issues and questions

Hello, My parents received lump sum pay out from my brother's pension who passed away in 2020. Because it passed 2 years since the date of his passing, there was emergency tax deducted which we were told my parents can claim some of it back, by filling R43 form (for tax claims for non-residents (they're polish). I've got multiple questions regarding this, I've tried to call HMRC but the call dropped multiple times and I still have no answers. - My father filled the form online and didn't save the right PDF (saved as online version of filled form, not the actual R43 filled form), so the access to it expired and he couldn't get the correct filled form downloaded. Can he fill it again, since this has to be sent by post and there was no reference number for online submission? - My both parents were beneficiaries with exact same amount (the total lump sump was divided by 2 - 50% / 50%), I understand they have to fill two separate forms in their names and this needs to be sent separately as well? Or both forms can be attached with supporting documents in one envelope? I would really appreciate help with this. Thank you, Iwona - My parents received P45 document from Royal London, after receiving lump sump for HMRC records as "leaving employee". That's of course not relevant as their never lived in UK and only receiving this due to their son's death who lived in UK. Do they have to report anything or can it be left, since it doesn't apply to their case?

Hi iwonaw,
Your parents will have to submit separate claims for a repayment of tax.  They can submit their claims together in the same envelope, but will need to ensure that all the documents can be easily separated into two claims. They should include the P45, but keep P45(1A) for their own records.  Repayments from HMRC are made in pounds sterling only.  If your parents do not have a UK bank account, they can nominate a trusted person to receive the payment on their behalf, by confirming this in writing.
Thank you.