The company is obviously stalling because it doesn't want to pay. There may be statute of limitations issues, which could prevent you from recovering some or all of your profits due if you don't sue by some date certain. So, the stalling may have a strategic action which could destroy your interests.
If the Will demonstrates that the estate owns the lease rights, then the company has the duty to pay the estate. If the estate is closed and contained pourover trust provisions, and you are the beneficiary of those provisions, then providing a copy of the trust will identify the trustee to whom payment must be made.
So, there is some justification for identifying the trustee, by means of a copy of the trust or duly recorded abstract.
You really should consider bringing all of the documentation to an attorney who knows oil lease law in particular, and fast, because you could find out that money is draining right out of your pocket here as the statute of limitations runs, and you may want to show the company that you are done screwing around with this, and that if you don't receive payment in full by date certain, that you are filing suit.
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