WHo said you will do that? Oo
I mean Tiri is already corrupted, she will be even happier because the fact that she is an Old God servant and you hate them makes her extremely said and is a lot of stress for her. Namalort is an Old God already, so he will be happy his father joined him!
Shandi... dont know about her, but she will either continue to serve you, but be as far as she can from you or just disappear horrified by the corruption and then come back to serve you. She may become your priestess or herald.
The only problem is Ronnie in this situation.. he will flee, but you will try to get him corrupted to be your herald or something.