I don't think Wave's reasons for deferring their report seem quite substantial enough to explain it. That's my sense.
I have another thought. Just a speculation.
The auditor has told Wave they need to show they have, say, an extra $7m in the bank in order to have the going concern qualification removed. GC is forward-looking, so knowing the money is there would help persuade the auditor they are not exposed.
Why this year? Removing the GC qualification would be helpful if Wave is trying to secure government business, I'd think.