As mentioned elsewhere if crankshaft sensor fails there is no attempt for the rev counter to move, as in it doesn't even try to show engine cranking revs.
My personal experience with crank sensors has been they usually fail when engine warm and then after cooling engine can restart. Many years ago I had a customer with a Vauxhall Corsa 1.2 which frequently died at the same junction on her way to work, each time I got there roughly 20 minutes later, car would instantly restart. Wasted time and money with so called diagnostic specialist, in the end took it to dealer, fault located and cured for less than the cost of specialist. I appreciate these days diagnose is more effective.
I did have similar with a Doblo 1.9JTD which died at 60-70mph, I coasted down a side road, nothing obvious under the bonnet and 10 minutes later it restarted so able to get home and ran diagnostics which pointed to crank sensor which I fitted and no further problem.
I have no experience re Camshaft sensors apart from reading about Nissan I believe, with stretched timing chains which would throw up a camshaft sensor code as the ECU read a mismatch between cam and crank but engine still ran although obviously needed expensive timing chain job, which turned out to be a common fault on that model.
It is always harder when not at vehicle, however from past experiences with after market anti theft systems, my suspicions would be in that direction.
