In 19.319 form:xforms-submission, ODF 1.2 says:
"The form:xforms-submission attribute specifies the name of an
<xforms:submission> element for a <form:button> control."
I rather doubt that because there is no <xforms:submission> element.
We do have the attribute form:xforms-submission on <form:button> but the
question is what is it specifying a name for?
My suspicion is that it is the name for the content submitted with the
form:button is selected.
Or as I suggested to Francis:
"specifies the name of a submission by a <form:button> control."
So the submission can be referred to by the processor and returned with
that name to its producer.
But that is only speculation on my part from the text.