What about the Best Buy warranty through geek squad? Would they just replace it with a new one if they can’t fix it?

Maybe. Reviews here have been mixed and seem to vary with time and location. Overall, the recent reports here indicate that getting something replaced under either an original factory warranty or under the subsequent third-party extended warranty/service contract coverage is often a drawn-out and arduous process.

Before further considering a Z-line range, you might want to check out these long-running threads here if you have not already seen them.

https://www.houzz.com/discussions/5965175/problems-with-zline-range#n=420

https://www.houzz.com/discussions/4967444/anyone-have-a-zline-range#n=1038

Thor is a marketing entity whose products are made by Hyxxion in China which also makes the versions sold by Kucht and NXR (also marketing entities.) The advice for these brands has often been that both warranty support and post-sale service have been such that you consider these brands only if you are handy at DIY repairs and are comfortable sourcing generic replacement parts. Of the three brands, NXR has been around the longest. Threads on it go back more than a decade here. For an example, see this long running NXR thread: https://www.houzz.com/discussions/2288437/if-susan-fixed-her-nxr-oven-ignitor-u-can-2#n=82 

For most, if not all of these brands, when you purchase one of their products, you are essentially buying something that is disposable. The chance of getting any kind of reliable service, whether under warranty or after the warranty. Is very slim. Not sure what your budget is, but I would consider touching base with local appliance service companies in your geographic area and ask them what brands are more practical to get serviced both with labor and parts. Warranties are only useful when there is a service network behind them to support warranty claims. Extended warranties are actually not warranties at all, but Service contracts that have little to no State regulation behind them and also remember that your time, like everyone’s, is valuable. If you have to spend hours and hours trying to extract a claim out of one of these warranties, that turns out to be quite an expensive warranty when you consider the bewildering amount of time, you will invest trying to get any kind of warranty work done, and that’s if you succeeded at getting them to honour their warranty at all. “Look before you leap”.