How to go about getting a second opinion?

I was diagnosed with a Bosniak III cyst in 2023, the leading / nationally renowned urologist I met with at the time said he wasn't concerned and thought it was probably a fatty benign cyst.

Most recent imaging upgraded to a Bosniak IV cyst and they're now recommending surgery although said I can wait if I want to since it's still just under 2cm (point at which they normally recommend surgery).

I wanted to get a second opinion -- mostly to ensure the radiologist didn't misread the imaging (and that it is indeed a IV, and not still a III) and also to make sure the next steps of surgery - but not necessarily urgent surgery - were agreed upon.

But I am having a heck of a time trying to find a way of scheduling a second opinion. I called a few cancer / renal centers today and they all need referrals... I feel like I don't necessarily want my original doctor to know I'm seeking out other opinions. Don't want to seem like I don't trust his advice, but I have OCD and getting a 2nd opinion would give definite peace of mind.

Not sure if anyone would be able to help give me recommendations on doctors but I'm in the state of PA (about an hour from Philly) if anyone happens to have any recommendations or advice on how to go about scheduling a second opinion.

Cheers.