They are possibly not going for the individual tones, but rather taking a range of impulse responses (IRs) plus the original timbre. From that, they may be able to digitally reproduce the sound - or else use an ordinary violin, and colour the sound with the Strad's IR to recreate similar waveforms.
Above reference discusses some of the issues for digital pianos - which are well-established and it is easy to find demonstration models in music shops.