The time to disburse sale proceeds to heirs varies. You don't say if the house was in a Will, Trust or joint ownership. The mention of ‘executors' indicates probate, but you say it's not in probate.
Under Oklahoma law, you cannot avoid probate by making an unofficial agreement to sell property titled in your mother's name. First clarify how the house was titled at the time of your mother's death:
• If title to the house was in her name when she died and she had a Will naming your siblings Executors or no Will, probate is required. For them to be legal executors a Court Order had to occur and the siblings agreed to serve as executors. Though it can happen earlier, often nothing is distributed until after probate.
• If the house was titled to a Living (Revocable) Trust and siblings were named Trustees, they could sell the house without a Court Order. Under a Trust, there is no probate and no executors, but it names Trustees to decide the handling of its assets, before and after the Trust's owner dies. Depending on taxes, claims, the inclination of Trustees and speed of lawyers, the money can be distributed right away or they can take their own sweet time.
I see you don't feel able to trust those handling this property. Sadly, sometimes executors and trustees take money and don't communicate. It's important. Follow up. Engage an experienced attorney to help unravel things.
If not ready for legal representation, then stop making calls that are being ignored. Write letters. Be polite. Specifically state the dates you spoke to people, their names, and exactly what they said. Ask nicely for an explanation for the delay within 5 business days of receiving the letter. Send it "return receipt requested." Copy your siblings. Keep a copy.
If you don't receive satisfactory response within a few days of your requested date, hire the best lawyer you can afford.
To your success,
Gale Allison, Principal Attorney
The Allison Firm, PLLC