I would assume that Trustaff has probably done some DD on MCTH as they agreed to the deal. Sometimes, however, privately held firms (like Trustaff) are not very sophisticated when it comes to selling their companies and they may not be asking the right DD questions.
More importantly, if MCTH had $26M in cash sitting around (or access to it via debt) they are required to report it in their SEC filings. This leaves one of two possibilities: (1) they don't have the cash and are now trying to figure out how to raise it (2) they've raised a significant amount of cash - seriously diluting shareholders - and are not reporting it to the SEC. Take your pick.