use of HAD in "BEFORE" sentences

[mmslf75]

Source: KAPLAN test CAT 4
Sentence #1
The limousine driver waited before deciding that his client is not going to turn up... -> This is the correct answer.

None of the answer choices had a "HAD" anywhere in the sentence

On the other hand, there was yet another sentence ...
Sentence #2
Couples that were married or engaged at the time of survey "had" lived together before making a final commitment...

The answer choice had "HAD" and other simplepast tenses...

Does BEFORE always indicate an anterior time thus signalling the presence of "HAD" in a sentence ?
And that, since we did not have an option with "HAD" in the first sentence, we had to choose the sentence with simple past(waited) and ( deciding - preset partciple ?

[capnx]

had needs to logically indicate a time period that is before/prior to another PAST period.

in 1: he limousine driver waited before deciding that his client is not going to turn up.

the time reference here is present tence, so a simple past tense to indicate sufficient.
if the sentence had been: ...that his client WAS not... then I think "had" would be required.

in 2: Couples that were married or engaged at the time of survey "had" lived together before making a final commitment...

clearly the time reference is in the past, so the logical sequence is: couples lived together, couples got married/engaged, couples took the survey. to properly express that the couples' living together is the furthest past of all 3, use had.