I don't think there is. The only sub-elements you can use from TON_1 are the output (.Q) and the rising edge of the input (.REDGE).
Evaluating the elapsed time <> 0 would be an easy workaround to read.
Another workaround would be to replace the TON with an program-scope BOOL tag, then put that tag in an XIC with the TON on a separate rung.
Coming from the A-B operating systems and syntax, using PLCOpen or ISAGraf is always an exercise in modifying your thinking to fit the toolset.