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I smell bullshit. Maybe unintentional... but yeah. No way he felt a shudder.
lets start with the communication system.
The Titan used an acoustic link system to communicate with the support ship. basically, it's like Sonar. only the sonar has been modulated to carry data. at the best of times, it can carry HD video in a somewhat live stream. but that's the best of times, and the Titan sub would have had to passed below the thermocline, which plays merry hell with sound. (military subs use it to hide, for example, because it significantly dampens their signature; or out right blocks it.)
this means their communications would have been spotty and sporadic, and basically limited to text updates. There's no reason to believe the sub imploded at the time of the last transmission. How much time passed... I can't say... though.
Secondly, it's almost impossible for them to have felt the implosion. Maybe hydrophones picked up the implosion, but that's about it. at more than a few thousand feet, it would have had to been a massive implosion to be felt on the surface. Sure locally, it was quite energetic, to say the least (things flashed into plasma under the adiabatic effects,)
Finally, they didn't know what happened. It wasn't until weeks later that the Navy came out saying they heard the implosion. If the support ship had felt the shudder, it would have been heard by it's hydrophones, and they would have had a much easier time learning what happened.