I don't understand why or how the partnerships selling wells before, during or after death applies to your beneficiary or what you are asking. You are not working on the Partnership's return. If there is some consideration to the deceased partner's interest because of the changing status at any point in time of these deals, I don't see it. The partnership simply carried on as usual, and whatever it did is reported on the K-1(s). Is this a red herring or not? Is this being reiterated because it is used to determine something?

On first pass, it seems that the partnership operated as usual, the deceased's interest passed into a Trust, and later the Trust distributed funds from the partnership interests (as it should) and the Trust would still be the partner. It isn't clear if or when partnership interest transferred from the Trust to the two beneficiaries as individuals. Or, a Trust Company was executor of the will, but there never was a Trust.

@PhoebeRoberts 

I am placing this callout to Phoebe, because I cannot determine what the partnership controlled, what the Trust controlled, and what you determine to have been inherited. It's a bit wordy to follow, because I think some of what is in there doesn't matter. Sorry. Let's see if Phoebe can help.