How do you know it is $25K off?  Have you seen any documents that indicate that?

You realize that whats shown on the K-1, may not be the same as the distribution of money that was received, right?

Yes, I have seen the real estate closing statement and the estate doc stating client is a 1/3rd heir. Also statements from client and brother that this was the only asset

Right, distribution is a separate issue

If the accountant and executor are ignoring the beneficiaries, maybe a call from the beneficiaries' attorney will get them to be a little more talkative.

Yes, they talked with their attorney who suggested a law suit is the only sure way to get the accountant and executor to talk. The amount they inherited could be easily eaten away by legal fees. 

Personally, I would get another heir, a couple of tents, and camp out next to the front and back doors of the executor and wait for him or her to do a little explaining.

Did the estate go through Probate?

Perhaps a call/]inquiry to the Clerk of the Court would be in order.

Everything was in a trust and bypassed probate.

Then your statement "A client received a K-1 from an estate for 2023 tax year" is incorrect.