I haven't used it on a car but have used a similar product to repair corrugated metal roofs, providing the surface is clean it will last for decades. What I used had a  thin aluminium foil to reflect the heat of the sun. There is absolutely no reason that due to being thicker than Dynamatt it will not be equal or even better at damping panel vibrations.
https://www.amazon.co.uk/Bond-Flashing-Tape-225mm-10Metres/dp/B0057FU69I/ref=asc_df_B0057FU69I?mcid=705e1e13a54d38439eba36997cef9ec5&tag=googshopuk-21&linkCode=df0&hvadid=697313183651&hvpos=&hvnetw=g&hvrand=6121744564645961281&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9212541&hvtargid=pla-740920208825&psc=1&gad_source=1

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