Interesting report!
Note that the file that is crashing here (C:\Users\funsize.cargo\bin\cargo.exe) is the rustup cargo proxy, not rustup itself (edit: *cargo itself).
This is curious because presumably rustup-init.exe ran successfully, and the rustup proxy is literally the same binary, so it's something on the proxying path that is crashing.
I assume that cargo itself does not crash. You can test by running C:\Users\funsize.rustup\toolchains\x86_64-pc-windows-msvc\bin\cargo (or something like that).
If you installed via the normal route that your rustup should be a 32-bit executable (I can't tell from your log), so as an experiment you might try the 64-bit version, which can be installed from https://static.rust-lang.org/rustup/dist/x86_64-pc-windows-gnu/rustup-init.exe (don't worry about the 'gnu' here - it just refers to the target used to build rustup itself; though you could also try the various '-msvc' builds of rustup here).