I am not an accountant so by no means claim to understand this,...

I am not an accountant so by no means claim to understand this, but the below seems to point to the cost being part of the reverse acquisition? So I don't think they actually spent $5M on "stuff".

The transaction has therefore been accounted for as a reverse acquisition from a consolidated perspective, where SenSen Networks Pty Ltd is the accounting acquirer and SenSen Networks Limited is the legal acquirer. The preliminary final report includes the consolidated financial statements of SenSen for the full year and the Company for the period 18 October 2017 to 30 June 2018. The annual report represents a continuation of SenSen Networks Pty Ltd.’s financial statements with exception of the capital structure. The amount recognised as equity instruments in these consolidated statements represents the issued equity of SenSen Networks Limited adjusted to reflect the equity issued by SenSen Networks Limited on acquisition. Refer to note 14 on issued capital.

Under the reverse acquisition principles, the consideration provided by SenSen Networks Pty Ltd was determined to be $10,306,942 which is the deemed fair value of the 103,069,423 shares owned by the former SenSen Networks Limited shareholders at the completion of the acquisition, valued at the capital raising share price of $0.10 per share.

The excess of the deemed fair value of the shares owned by the SenSen Networks Limited shareholders and the fair value of the identifiable net assets of SenSen Networks Limited immediately prior to the completion of the merger is accounted for under AASB 2 Share Based Payments and resulted in the recognition of $5,229,773 being recorded as “Corporate Restructure Expense”. The net assets of SenSen Networks Limited were recorded at fair value at acquisition date. As the carrying value of all assets and liabilities held by the SenSen Networks Limited at acquisition date approximated their fair value, no adjustments were required.