Well I haven't talked about this too much, but I actually did a timeline for Durin VII and how old he would be by 3018. 2866 Thorin III was born, and if he had Durin VII at the same age as Dain had him (99 years old), then by 3018 that puts Durin VII at 53 years old.
Now if we continue with the timeline, he is 56 when the Third Age ends and he is 176 years old when Gimli and Legolas leave for Valinor. So assuming the 4th age goes on forever (since we don't know when it ends) and Durin VII has the longevity of the Durins, it is most conceivable that Durin VII is the descendant of Thorin III as he is his son. Durin I lived over 2,500 years, Durin VI was 249 and was ruling in good condition until the Balrog killed him. We are not given any real dates as to how long Durin III-V lived.
So assuming the minimum years being 250 (like Dain) that would put Durin VII at 194 of the Fourth Age. However, we must remember Dwarfs are hinted to live an average of 250 years, Durin's line is longer, and Dwalin lived to a rare 340 years.
So in conclusion, as I have stated, I strongly feel Durin VII would have to be the son of Thorin III, given the short amount of time Dwarfs existed in the 4th age, the longevity of Durins, and the sequences of middle earth's timeline.
I appreciate the feedback from everyone and I too strongly feel that Durin should be brought back to Edain Mod. If not in hero form then at least if King Dain refuses the One Ring.
Durin VII IMO should be the best Dwarf of the Game, that is not to say the best hero or character, he should be better than Thorin II or either Dains.