Regrading Division 7A : Section 109BC explicitly states that it is applicable to non-resident companies.......
Regarding section 99B: there is a significant volume of case law which discusses that 'distributions' from discretionary trusts are indeed gifts. Not that it actually matters for s 99B.
For section 99B to apply there merely needs to be a payment to a resident beneficiary (I note that the actual amount subject to tax in Australia is not merely the quantum of the payment). Trust deeds can be drafted quite broadly in terms of who is a beneficiary and it is quite possible that the OP would in fact be a beneficiary of the hypothetical trust we are discussing.
It is due to these complexities and nuances along with the potential application of other rules (i.e. temporary resident rules which may carve out any such income) that I suggested the OP see an accountant
The fact of the matter is that if the 'gift' came from an entity then there is a risk that there will be tax consequences.
