Hello,
I’m a medical writer with a PhD degree (classified under technical writers job code). My wage level is 2, and my attorney is very confident that my petition maybe rejected, or at least receive an Rfe. 
Does anyone here have any idea if any such cases Have been approved?
Your attorney is mistaken. Your petition might attract an RFE but this is not because of wage structure, it is simply because all petitions these days are attracting an RFE. A PhD allows you to occupy a niche area in technical writing but the advanced degree or choice of profession does not allow too much of bargaining in wages. Please visit the wage and qualifications website www.Onetonline.org to know more. O-Net is very helpful for you to understand the wage range for any job.
Many thanks for your encouraging response, Shankar! I was highly stressed out because they asked our company to conduct a prevailing wage survey, and all the wage survey companies also use DOL codes for technical writers to do so. Medical Writing is not independently looked at in these wage surveys. So there is no clear way for me to prove that the wage is in accordance with the industry standards. My employer uses PayScale to determine the wages and attorney said that won’t be acceptable. Given the tight timeline to file the Labor petition and then the H1B, I felt this was a lot to worry about.