CW-
I did a little research, and the CSR (Code of State Regulations) are a little more clear and are the actual regulations enforced in court. The little color booklets are a summary which are not necessarily legally correct (and are disclaimed as such I believe).
This is taken from the Secretary of State website, who is the keeper of codified laws. I have taken the applicable excerpt. It can be read in entirety at:
www.sos.mo.gov/adrules/csr/current/3csr/3c10-7.pdf
"3 CSR 10-7.410 Hunting Methods
PURPOSE: This rule prescribes the methods
by which wildlife may be hunted.
(1) Wildlife may be hunted and taken only in
accordance with the following:
(B) Artificial Light. No person shall throw
or cast the rays of a spotlight, headlight or
other artificial light on any highway or roadway,
whether public or private, or in any
field, woodland or forest for the purpose of
spotting, locating or attempting to take or
hunt any game animal, except raccoons or
other furbearing animals when treed with the
aid of dogs, while having in possession or
control, either singly or as one (1) of a group
of persons, any firearm, bow or other implement
whereby game could be killed.
(L) Electronic Calls. Electronic calls may
be used to pursue and take crows and furbearers,
but without the aid of an artificial light or
night vision equipment."
So according to this you could use the electronic calls at night, just not a light. Hope this helps, or at least makes things clearer.