How many valuations have you done in which you could not get industry data? This happens to me maybe one in twenty times. (I use First Research, IbisWorld and BizMiner, in addition to contacting trade associations.) This usually happens with companies that offer highly specialized products and services or which serve unique, small markets. It also arises when the subject is a small part of a very large, diversified industry with many segments (e.g. chemicals). A recent example was a company that provides custom chemicals to dairy farms. There was nothing in my sources about these niche producers.
When this happens, I have found it very helpful to research the end-user industry. This gives me good insights into demand and pricing trends, even though I do not have much to say about the industry itself other that what I glean from the business owner.
Caution! Do not use end-user data for market guideline transactions / companies, or for comparative financial data. A chemical company is very different from a farm!