A bit late, but you can use something like a std::sync::atomic::AtomicU16 or just a static mut u16 as like a question counter, and then just return false when that counter hits a certain value.
The only slight issue is that Rust tests are run in parallel, but I'm assuming only one of the test categories are timing out, so this should be fine.

You can print the input and then force flush stdout, which should ensure the printed input will be displayed even if the tests have timed out.