Does " vague innuendoes" here mean "vague suggestion in his mind"?

Does " vague innuendoes" here mean "vague suggestion in his mind"?

It was difficult to say which was the more annoying: Houdini the conjurer, with his preposterous and ignorant theories of fraud, or such "scientific" sitters as Professor McDougall, of Harvard, who, after fifty sittings and signing as many papers at the end of each sitting to endorse the wonders recorded, was still unable to give any definite judgment, and contented himself with vague innuendoes.

"The History of Spiritualism," by Arthur Conan Doyle