I am not sure if your issue is with the slips themselves or the T619 at the top of the XML
this link below is for the T619 part common to any type of slips
https://www.canada.ca/en/revenue-agency/services/e-services/filing-information-returns-electronicall...
this link below is the XML specifications for T5 slips or T4
https://www.canada.ca/en/revenue-agency/services/e-services/filing-information-returns-electronicall...
you will find ... for the T5 recipients
Recipient Business Number (BN)
- Required, 15 alphanumeric, example: 000000000RT0000, or 000000000RZ0000, or 000000000RP0000, or 000000000RC0000
- T5 slip, box 22
- 9 or 15 digits of the recipient’s BN assigned by the CRA.
-When the recipient has failed to provide an Account number, enter [removed], or 000000000RC0000, or 000000000RZ0000, or 000000000RT0000, or 000000000RP0000 in the field
