Yes forget about an investigation as you would be relying on the honesty of Chinese officials and they have proven to have a vested interest in hiding the truth , same happened with the passenger jet that got hit by a missile over Ukraine by a Russian made missile launcher , the Russians lied through their teeth .
Just counter slam a tariff on all Chinese imports to pay for :
1Covid
2 the increased cost Australia has to now pay for transiting its shipping through the China sea
3 the effects from green house emmissions that China is pumping into the atmosphere with a new coal powered station going on line every 12 days in China
4 put in place an OPEC style agreement with Brazil for all exports of iron ore to China