My suggestion was to move 3.11.2 xjdf:GeneralID - Payment to be a subsection of 4.2 Payment. See the final row in table 4.2 Payment Element:
|xjdf:GeneralID *||element||Additional identifiers related to the Payment.|
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4.2.1 xjdf:GeneralID - Payment
This section specifies particular Payment values for xjdf:GeneralID/@IDUsage in the context of Payment..