I'd be interested in seeing what they told you about the prior art. Somebody may be glossing over important details there.
Just to add, yes, you can deduct those expenses for the most part, as research-and-experimentation. And yes, the deduction can offset your project expenses, depending on your tax bracket. But, it's best if the expenses themselves add value to the project. For example, if you invest in a patent, or inventory, or the like, then you will be adding value to your project
and deducting income. However, if you invest income on some dubious process with no guarantee of any added value, then the tax deduction doesn't really benefit you.
You can read more about tax deductions from an old article of mine
here.