Your reasoning seems unavoidable.
The "snap effect" prevent a slow fusion in a two body mode. If a snap happen, the energy will be released brutally.
Alan push an alternative, nuclei are delocalized, at least some quarks are...
Digging in conjectures...
Only way to avoid the snap effect is to have a very local opposing force (usually with magnets it is my fingers who play the counter potential).
Strong force can be opposing... In some article I don't understand much, I've read that the core potential tower of strong force is due to W boson exchanges... Can electrons screening ineract with nuclei, to make the core potential stronger ?
Opposing force may come from positivey charged particle orbiting near the nucleus... crazy.
Maybe a strange lobe of nucleus wave...
if you think in 1D constrained system, the lobe may be very local...
Funny how all seems impossible.
Again experiments are needed to clear out the impossible and orient to feasible ideas matching reality.