Is applying vaporub or Vicks inside the nose unsafe even if it helps you breathe better for who has asthma?

Maybe. There have been reports in young children of serious infammation of the lungs caused by inhaling this stuff, requiring hospitalization. And it probably does not help anyway.
Probably not. Interestingly vick vapor rub does not make you breath easier. It appears that this compound fools your nose into thinking that it is easier to breath and less congested.
No. Having said that it isn't unsafe doesn't mean that it helps. True bronchoconstriction is only relieved with beta agonsits like xopenex (levalbuterol) and albuterol. Airway swelling is only relieved with immune modulators like steroids.