To summarize: sheet2 contains a number of formulas, one of which
performs the proper calculation to determine the sling load. Sheet1
cell A1 needs to display the result of the proper formula from sheet2.
Do I have that right?

If so, you might set up a new column on sheet2 with a header "Correct
sling load calc" such that the new column is right next to the output
of the 6 formulas. Then enter an X next to the correct formula, and
set up Sheet1!A1 as a VLOOKUP formula that returns a value from sheet2
if there is an X next to it.

Is that feasible, or even in the right ballpark?