According to a previously submitted RFI, the TA1 can be used as a response to a transaction with an unreadable ISA segment. The TA101, TA102, and TA103 are all required elements that echo back the interchange control number, date, and time from the original transaction. In the case that these elements are absent from the original interchange, what is expected to be populated in these fields on the TA1? The only options appear to be to violate the requirement rules or to populate default values such as returning all 0's in the TA101 and the file process date/time in the TA102 and TA103.
There is no way to construct a properly formed TA1 segment when the Interchange data elements that you cite are missing or corrupt. As a result, the response to unforeseen situations is always dependent on trading partner agreement. Some trading partner agreements may make accommodations for technical situations such as these and could involve default values or out of band communication channels. The prior RFI was specific to the 4010 implementation and is no longer a valid or relevant interpretation with regards to the 5010 standard.