I suppose in theory, though I'm not an expert. It sounds logical!
If you weren't 'fooling around', what were you doing when you ejaculated? How long after that did you insert your finger in her vagina. Sperm only live for a few hours outside the body.
If you rinsed your hands really quickly, you might not have got rid of all the ejaculate, in which case she could get pregnant.
It all comes down to how well your hands were 'rinsed' and 'toweled'.
Lots of detail missing. You (alone) went to the bathroom but you (both) went back to the room. What happened in between?
You (both) went back to the room and then you just pushed your finger in her?
However, you have been to the bathroom, handled toilet paper, and only rinsed and didn't wash your hands with soap? If you did not transfer ejaculate into her vagina, you may have transferred toilet germs (like e-coli) from your unwashed hands!!
You have picked up a 7-month-old thread! So which post are you referring to in your question?
You are not very clear in what you are asking, so please explain a bit more exactly what you mean.
1. What do you mean by 'disvirgin'?
2. How exactly do you intend to disvirgin her?
3. What have your hands been doing previously?
4. What will they be doing when you disvirgin her?