Ye gods, the things kids these days worry about... I'll just be nice and tell you what happens: the audit somehow finds its way to get itself signed because:
1.) nobody wants to budge on the deadline so, it'll get itself signed somehow whether by closing one eye to cutting corners or some silly guy or two tanks it because someone didn't want to close one eye.
2.) in some cases, someone budges on the deadline so no corners needs to be cut or the silly guy doesn't have to OT as much as he would've otherwise.

Keep in mind nobody except ACRA reviews audit files. Sometimes. There's no stakeholder to submit your workpapers to. People just want their FS signed because they need it. Back then FS gets signed even when audit is not completed but nothing happened. No one cares about the quality of audit because their accountant is expected to have a baseline knowledge at preparing an FS anyway.

Please don't sacrifice your health for other people, much less so for a job that doesn't even pay you enough to FIRE. But be realistic that if you need the paycheck, just do the bare minimum to protect yourself because let's be honest, everyone is too busy to fire you until they're mandated to do so during performance review.