Welcome to the community, @allenn!
You might not need to buy a new cooktop. The glass top is often quite a simple part, just the glass pane without embedded or attached electronics. If so, it might be easy and relatively inexpensive to replace.
At least, that’s what we found when the glass top on our Bosch induction cooktop cracked (after the heavy stainless steel rangehood filter was dropped on it - by fumblefingers me 
).
The part wasn’t expensive, and - pleasant surprise - our house insurance covered the full cost of the replacement anyway, including the technician callout.
So - I suggest you find out whether the same applies to Westinghouse, and also ask your insurance company whether your insurance covers this sort of thing.
As for why it cracked: glass can sometimes crack seemingly at random. Toughened glass in shower screens, table tops, etc in particular is known to just suddenly shatter for no apparent reason. We had that happen with a glass-topped outdoor table, and I know someone whose shower screen door did the same thing, fortunately not while someone was showering.
Glass cooktops are very heat-resistant, but brittle. A knock can break them, and a little chip on the edge could be enough to generate a crack as the glass heats and cools in use. It is not difficult to chip those exposed edges.
If I were buying a new induction cooktop now, I think I’d look for one that has a metal frame to protect the edge of the glass.
We’ve been happy with our Bosch cooktop, in spite of the cracked top. Bosch makes things to be repairable. Parts are available for years, and not expensive when repair does become necessary. Other than that - which was my fault - our cooktop has been very reliable.
