If they called you and told you, and you ok’ed it, then you will have to pay in my eyes.
If they called you and you said “hey guys wtf, i’ll give you 1/2 because i feel the part could have been 1/2 fucked and that your mechanics are 1/2 fucked” then i’d say you owe them half.
If they did it without you knowing at all, i’d throw them a huge “place your lips on my nuts” sign.
I would want the alignment free as well as labor, and just pay for the parts.