Naphthalene acetic acid is not a plant hormone, it is a plant regulator (synthetic compounds). So try your experiment to see what will happen .

Naphthalene has been used as a fumigant pesticide in soil as it builds up toxic fumes and can kill larval and adult forms of moths. Same use for domestic purposes, for example to keep clothes free from moths. Not clear if you are going to put your plant also inside the bag or outside - if it is outside, I don't think it will have an effect. Naphthalene is the precursor to many synthetic compounds and people generally use derivatives of naphthalene rather than the product itself on plants.Anyway, a good idea to test what happens - keep us posted of the results.

Thanks