Can a table salt + vinegar mixture be explosive?
Of Course NaCl is the Salt of strong acid and strong base . It is very stable . Even if you take any amount of NaCl with Vinegar it will not do any explosion .

It may be the baking soda (NaHCO3 ) and Vinegar , As this reaction is a neutralization reaction (Exothermic) and accompanied by the formation of CO2 , If enough concentration is taken it can burst a plastic bottle on applying some pressure . 

https://www.youtube.com/watch?v=UclxSfPoapc