Is this rude and would you be offended by this message?

If I was your mom, I wouldn't call them back. They haven't wanted to talk in all this time, to heck with them. If they called again and brought up the above, she needs to tell them where you work and what you do is your business, not theirs and do they expect everyone's name who works for this company be posted for all the world to see. Then end it....no need to get into a family feud about it. Don't worry what they think.....they are not worth it.