Merriam-Webster

Hello, everyone! I have a question concerning the online version of Merriam-Webster’s Collegiate Dictionary, The Chicago Manual of Style’s preferred dictionary. Now, in this answer to a question about whether to use OK or okay, the word okeydoke is present near the very bottom. Now, CMOS likes to use the first form of a word in almost every case so as to be consistent, but this is a variant of okey dokey that’s way down the list, which strikes me as a bit odd. I then checked out the thesaurus definition, and—lo and behold—okeydoke is the preferred term. First, it seems odd that there are two separate preferred terms for the dictionary and thesaurus versions of Merriam-Webster. Second, it appears to be a discrepancy on CMOS’s part since they prefer the first form of the dictionary version of a word, not the thesaurus one. I would really appreciate it if you guys would help me out.