It is not a horrible translation, you want to make it a horrible translation because you want to not accept that the bible says all over it that disobedience is a sin of unbelief.
Hebrews mentions both unbelief and disobedience. Note that the major issue is entering God's Rest, which means not working!
:16 For who, when they heard, did provoke? nay, did not all they that came out of Egypt by Moses? 17 And with whom was he displeased forty years? was it not with them that sinned, whose bodies fell in the wilderness? 18 And to whom sware he that they should not enter into his rest, but to them that were disobedient? 19 And we see that they were not able to enter in because of unbelief.
[I know of no dispute on the translation here.
Behind the disobedience was a failure to trust the Lord -- they cited giants in the land.]
4:1 Let us fear therefore, lest haply, a promise being left of entering into his rest, any one of you should seem to have come short of it. 2 For indeed we have had good tidings preached unto us, even as also they: but the word of hearing did not profit them, because it was not united by faith with them that heard. 3 For we who have believed do enter into that rest; even as he hath said,
As I sware in my wrath,
They shall not enter into my rest:
although the works were finished from the foundation of the world.
4 For he hath said somewhere of the seventh day on this wise, And God rested on the seventh day from all his works; 5 and in this place again,
They shall not enter into my rest.
4:6 Seeing therefore it remaineth that some should enter thereinto, and they to whom the good tidings were before preached failed to enter in because of disobedience, 7 he again defineth a certain day, To-day, saying in David so long a time afterward (even as hath been said before),
To-day if ye shall hear his voice,
Harden not your hearts.
4:8 For if Joshua had given them rest, he would not have spoken afterward of another day. 9 There remaineth therefore a sabbath rest for the people of God. 10 For he that is entered into his rest hath himself also rested from his works, as God did from his. 11 Let us therefore give diligence to enter into that rest, that no man fall after the same example of disobedience.
In the phrase, "because of disobedience," the term goes back to the verb peithō which means "I persuade," as opposed to the other standard term for obey (which means to hear, thus hear & do as you hear).
Consider that a failure to enter in is a disobedience. But to say that they failed to enter because of disobedience, makes no sense. You don't disobey because of disobedience. You disobey when you fail to trust the Lord. Thus I would translate that "failed to enter in because of not being persuaded."
The text already said they didn't enter because of unbelief. I think the KJV has it better here than other translations.
The word often translated "disobedience" here is a combination of the prefix a- (negative) and the stem/root for persuade, peith-. To be disobedient is to be "not-persuaded" literally, here. Which is another way of saying that one is not convinced by the Lord, one is unbelieving.
BDAG:
πείθω
1. act., except for 2 perf. and plpf.: to cause to come to a particular point of view or course of action.
a. convince w. acc. of pers.
b. persuade, appeal to, also in an unfavorable sense cajole, mislead
c. win over, strive to please
d. conciliate, pacify, set at ease/rest
2. The 2 pf. (w. plpf.) has pres. mng. to be so convinced that one puts confidence in someth.
a. depend on, trust in w. dat. of pers. or thing (here πέπ. w. dat. almost = believe in, a sense which πέπ. also approximates in the LXX; cp. Jos., Ant. 7, 122).
b. be convinced, be sure, certain
3. pass. and mid., except for the pf.: to be won over as the result of persuasion.
a. be persuaded, believe abs.
b. obey, follow w. dat. of pers. or thing
c. Some passages stand betw. a and b and permit either transl., w. dat. be persuaded by someone, take someone’s advice or obey, follow someone Ac 5:36f, 39; 23:21; 27:11
4. perf. pass. πέπεισμαι to attain certainty in ref. to something, be convinced, certain
“FAITH, PERSUADE, BELIEF, UNBELIEF,” NIDNTT, 1:589. (New International Dictionary of New Testament Theology):
1 The stem peith- (pith-, poith-) has the basic meaning of trust (cf. Lat. fido, fides). The same stem is also the basis of the formations with pist- ( πιστεύω). Trust can refer to a statement, so that it has the meaning to put faith in, to let oneself be convinced, or to a demand, so that it gets the meaning of obey, be persuaded. The original intrans. act. peithō (trust) became trans., to convince, persuade (already in the time of Homer), first through the pass. (be convinced, persuaded). The meaning to trust was taken over with both the above-mentioned branches from the mid. pass. peithomai. Only the 2nd perf. pepoitha retains in the act. the original intrans. meaning (strictly, to have taken hold of trust with the effect continuing into the present). It has the present meaning of trusting firmly, relying upon. The mid. pass. of the 1st perf. pepeismai (strictly, to have been convinced, or to have convinced oneself) likewise means to be convinced. The noun pepoithēsis (trust, confidence), derived from pepoitha is late Gk.