*** Her body has not decayed. For how long now? 200 years.***
Nothing new. Napoleon was buried without embalming, yet when he was dug up years later his body had not decayed.
It was attributed to arsenic poisoned wine he had been drinking over several years.
Maybe St Catherine was also embalmed with arsenic.
And maybe the Starship Enterprise went back in time and put her into a stasis chamber. Wait, wait, I got it: Maybe the "Flash" made her molecules vibrate so fast that she can't decay.
I will prove my theories after you prove yours.
Who the heck ever heard of embalming with arsenic?