Was my reply to my employee hostile?

2 days ago, I asked a worker to take a look at what was being sent out if she had time. After lunch on that day, she showed me the rude response from her teammate after emailing him, "Kyle, Your 29-way charts are illustrated way too small in Adobe and the 3rd item in the checklist needs to be removed.... show more 2 days ago, I asked a worker to take a look at what was being sent out if she had time. After lunch on that day, she showed me the rude response from her teammate after emailing him, "Kyle, Your 29-way charts are illustrated way too small in Adobe and the 3rd item in the checklist needs to be removed. -Nancy"; His reply was, "Do it yourself since you want the job done!" So, I told her to treat others the way you'd like to be treated. After I had her show me the entire email since Kyle recently stressed to get both sides, she was in the clear. So, I went up to Kyle to tell him that it was very rude. I returned to Nancy to tell her that I told Kyle that. I printed out his charts & brought them over to him. I showed him how it was impossible to read the #s in the circles. I returned to my seat & forwarded him, "I don't want to see an email like this again. Your response was very rude. I emailed each of you guidelines. Your diagrams fail to meet them. If you're unsure, please see me. What Nancy found are wrong and need correcting. These are not items that I would consider a personal opinion." Then I told his dad who's a worker in another unit, and Kyle probably heard about it from his mom. He replied to my email about a half hour ago, "I'd like to apologize for this. Nancy approached my area and was impressed that I spent only 4 hours on it. I was extremely irritated of something trivial being pointed out. I was concerned that it was taking way more time than it should because
Update: only a test point was added. Instead, I repeatedly caught things to delete and adjust so I must have overlooked them. Kelly checked it this morning." Kelly is another employee of mine. After I emailed back, "I am not the one you need to apologize to. I will not tolerate disrespect from any of you. Time... show more only a test point was added. Instead, I repeatedly caught things to delete and adjust so I must have overlooked them. Kelly checked it this morning." Kelly is another employee of mine. After I emailed back, "I am not the one you need to apologize to. I will not tolerate disrespect from any of you. Time has not been an issue," I thought about my reply. Now I'm wondering: Was I hard on Kyle?
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