How can I obtain a work invitation letter from my Thai partner for a non-B visa after my visa renewal was denied?

Hello, I am a resident of Thailand 5 years ago, I have a company and set up a business and VISA work, on 11/8/2017 visa will expire, I went with the lawyer to immigration , after checking the document refused to renew the visa again,The reason for the refusal is that the accountant pays the staff and hospital insurance less than the required 300 baht . The lawyer called and asked the accountant She told her that each year she paid the same amount and there was no problem, I do not know if she was lying or did not know the required increase, the immigration asked me to go outside Thailand And get a nonB visa and return again, but I am a Syrian nationality and I can only get a visa from Lebanon and the embassy in Lebanon asked me about invitation from company to working in Thailand how will I get a work invitation , and from who , I have already business her , just want to know Can I get a work invitation from my Thai partner, and do this Call her a specific name, and must be certified by the Thai Foreign Affairs, thank you so much