A lot more worse than that.
MLK avowed in his writings, he didn’t believe Jesus Christ had been resurrected, would ever return again physically, denied the doctrines of substitutionary atonement, repentance , and a number of other fundamental Christian doctrines.
http://www.jesustheboss.com/MartinLutherKingJr.html
He also had been understood to say the only reason he kept the title as a Reverend, is that it gave him a springboard to advance his political beliefs.
These little tidbits aren’t popular, because if you used them, those who amicably accept MLK as a great leader, will tend to label you as a bigoted ‘white supremist’ or as a ‘racist’.
Just as an FYI, Jefferson didn’t believe Jesus had resurrected or indeed was any different from, say, the Dalai Lama, and even denied a lot of supernatural elements, created the Jefferson Bible which utterly gutted the supernatural elements of God and Jesus, and I believe he sarcastically referred to the Triune God as a chimera if I’ve read him right. Yet we don’t denounce him and place him in very high regard as a man of freedom, and he undoubtedly was even WORSE than MLK in that regard (at least MLK had enough respect for the bible to not try and make a half-rate forgery in his name that outright gutted all supernatural aspects to God and Jesus, which Jefferson did).
If I had to choose MLK and Jefferson regarding who was ultimately a better follower of Christ, I’d stick with MLK. I would personally suggest you condemn Jefferson if you wish to be consistent.