Missing Tag depend on the invoice itself

In JDE 9.1. we have a BI template for Invoice. However, depend on the tax code ( no tax, GST, HST, Exemption ).. if the invoice has no tax, the <TAX_CODE> tag is missing from the invoice. However, when the invoice has tax_code, <TAX_CODE>HST</TAX_CODE> is in the xml file

Before I have to update the UBE to force the tag back. Is there a way in BI template to assign a 0.00% value when the TAX_CODE tag is missing for a invoice.