It would be nice to know if this is B2B or B2C; and if B2B is it a complex sale or a transactional sale? (The difference is that a complex sale has at least more than one person involved in the buying process.)
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Don't confuse something that YOU think is viable with what the market thinks is viable. The last thing you should do is to keep it a secret.

My suggestion is to find at least 25 and 50+ is a better number, people who you think might be viable customers for this idea and talk to them. (Note, I did not say PITCH it to them).

The first thing you need to do is to figure out what the specific problem is that your problem solves.

Then, figure out if people are willing to pay for it, and how much. (There are lots of problems that people just deal with daily that are not worthy of fixing).

Then, figure out what the best method is to reach that market, i.e. the people with that issue.

The key here is that you don't have to figure it out for yourself. These 25 - 50 people will give you the answers.

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If this is a complex sale then, I respectfully disagree with Lee. Yes, you need "testers" to make sure the product works, but you need to find the "Economic Buyer", i.e. the people who will be the buyers of your products. Testers are "User" buyers and can usually say "no" but they rarely can say "yes" and the sale is done. But, if it's a simple sale and the EB and the UB are the same person, then, Lee is correct.

Good luck and let us know how it goes.