Stack Exchange sites are not forums, where somebody can post a question about the question asked from the OP; the format of Stack Exchange site is question/answer, where an answer really provides an answer to the question being asked (and it is not a comment about the question). This means that posting something similar to the following will cause the post to be deleted.
- Me too!
- I have a similar problem: [description of the problem]. Can you help me?
- Did you find a solution for your problem?
- This is not the site where to ask this type of questions.
- What do you mean? I am not clear what your problem is.
Editing the question to add more details is not what you should do; you would add details for your question, not for the question asked from the OP. The block that suggests how to edit a post that is show to who doesn't have the privilege of editing any post reports the following notes:
- fix grammatical or spelling errors
- clarify meaning without changing it
- correct minor mistakes
- add related resources or links
- always respect the original author
If you add details that are not given by the OP, you are changing the meaning of the question. It could be that your details apply also to the question asked from the OP, but you are not sure of that, as you don't have any confirmation from the OP.
As you don't have the privilege of commenting everywhere (that is a privilege you get when your reputation is at least 50), and you cannot offer a bounty (you need a reputation of at least 75), you can only ask another question, reporting that you have already seen the other question, reporting the link to the other question, and pointing out the difference between yours and the existing one. This doesn't assure the question is not closed as duplicate because, if the community see little difference between the questions, the community will vote to close your question.
About your answer being deleted from a moderator, it is more probable that your answer has been flagged from a user as "not an answer" and a moderator deleted it once verified the answer was a new question. Moderators don't look for questions that are posted as answers, and rely for that on the reports done from the community. Of course, they first verify the flag is valid, and they will never delete a wrong answer, as it's not their task to give a technical judgement of the answer's correctness. If you see a wrong answer (which is different from something that is not an answer), then you should down-vote it.