I think you have a hot mess in your hands with a lot of potential for things to go wrong. In no particular order:

- The check-in staff at SYD will have to interline your luggage all the way to TLV, and I think the fact that it's all in one PNR will play in your favour

- There have to be no delays

- There have to be no queues in ZRH at security or passport control (this one is easy)

With 1h45 I think this is possible, but what I would do would be to buy some form of travel insurance that would cover the cost of new tickets and/or accommodation.

Keep in mind that if you miss your ZRH-TLV flight, the rest of the itinerary (i.e. at the very least TLV-ZRH, maybe even the return to Australia) might very well get cancelled because you will be considered as a no show.

Oh, and find a better TA or purchase tickets directly from the airline, I find things are much easier to fix if something goes wrong.