What I'm saying is that the K-1 is as good as it's going to get, that you can reasonably rely on the information on the K-1, and that the K-1 preparer acts as a non-signing preparer of your client's returns with respect to the K-1 items. What "reasonably rely on" means is a matter of professional judgement.
Those K-1s are like a game of telephone, where each lower tier entity reports information in a slightly different format and with a slightly different level of detail. The next tier up aggregates that information, generally without making any effort to make the format or level of detail consistent (which is why you'll see half a dozen line items for what's essentially the same item of income shoved haphazardly into some combination of 11A and 11I), because there are literally not enough hours in the day to do those returns. That K-1 goes another level up, and the process repeats. I've seen a couple with 20 lines of summarized depletion (some lines with unique labels, some with duplicative labels!) that need to be collapsed into some semblance of "allowable depletion" and "depletion in excess of basis," which are the only numbers likely to be relevant to your return. I've seen some that attached a thick stack of property-by-property depletion schedules that bore no relationship to the summarized totals. There is no right answer to the question you are asking, and if there were a right answer, there exists no single person who has ever has access to all the information needed to arrive at it.
> how would I know if the partnership adjusted for percentage depletion
> in excess of basis in the capital account
Not relevant. You calculate outside basis, the partnership calculates capital account, no reason why those two would be more than tangentially related (even under the tax-basis capital account reporting rules).
> if the tentative depletion is calculated using percentage depletion or
> cost depletion or a combination of both
It's a combination of both, because you get the greater of cost or percentage on a property-by-property basis, and no one only has winners. You enter it into Lacerte as percentage depletion, because Lacerte treats the K-1 as one property and gives you the larger of cost or percentage, not the sum of cost and percentage. This is a software limitation, and the input I suggested should get you the output you expect. You pick percentage as your one number, not cost, because there's no such thing as cost depletion in excess of basis, and even if Lacerte produced the desired output, your depletion schedule would look wrong.
Your guy's production is 7,629 barrels of oil equivalent. That's a lot of oil - 17D is probably around $800k? $31k is pretty much no depletion on that much production. It's entirely possible your guy's share of depletion is the sum of all those detail numbers: $69,879, of which $12,785 is in excess of basis.
