What is with these writers?
Miss Ellie gives half of Southfork to Jon Ross, years after giving the whole thing to Bobby?!?
#1 - The letter wouldn't be by any stretch legal to begin with, once given, it's Bobby's to do with as he pleases. The only possible way would be for that half to be held in trust, and the original will would have to establish that.
#2 - Okay, so if a share is given to J.R. son, why would Gary (her favorite) not get an equal share?
And Cliff allowing his daughter to be in danger? Sorry, as much as he hated J.R., his love of family was one thing Cliff was always constant in. There is no way he'd let any danger come to family.
Also, Barnes Global was started by his mother? Rebecca Wentworth inherited Wentworth Industries from her second husband (Katherine's father). Before she died she bought an oil company and gave it to Cliff (Barnes-Wentworth Oil), and later when she died Wentworth Industries was spilt between Pam & Rebecca (Cliff didn't get any since he already got Barnes-Wentworth). A third, smaller, company, Wentworth Tool & Dye was split between the 3 of them.
Cliff sold Barnes-Wentworth before he joined Ewing Oil. At the end of the series he bought all of Ewing Oil, but Wentworth Industries was controlled by Bobby (as Pam had given his power of attorney until Christopher was of age), and Katherine was still on the lam after shooting Bobby. While Pam easily could have gotten control of the company, Cliff has no part of Wentworth. So if anything, Barnes Global would be Ewing Oil, not Wentworth, so finding Pam should change nothing.
These writers really need to sit and watch the whole original series.