This is the only list we have, but at least you know it's 100% accurate as it stands today, because it's taken from the batch file that compiles the vehicles:
AA "K KDFW KJFK KLAX KMIA KORD" "AAL,AALX,LOF"
AAY "K KBLI KPGD KFLL KMYR KOAK KSFB KIWA KPIE" AAY
AB "ED ET EDDT" "BER" red
AC "C CYYC CYUL CYYZ CYVR" "ACA,GGN,JZA,SKV"
ADR "LIRF LIRA" "_ADR"
Aerogate "EDDM" "_ARGT" orange
AF "LF LFPG LFML LFMN" "AFR,AFRC,AFRX"
AHS "ED ET" "_AHS"
AI "VA VE VI VO VABB VIDP VOMM VECC VOBL VOCI VOHS VAAH" "AIC,AXB,LLR"
ANA "RT RJAA RJTT RJOO RJBB RJGG RJCC" "ANA,ANK,AJX,AKX,AJV"
AQ "PH PHNL" "AAH"
AR "SA" "ARG"
ARE "LI" "ARE Group"
ASA "KPDX KSEA PANC KLAX KSJC" "ASA"
ASDD "EDDC" "_ASDD" yellow
ASIG "K" "_ASIG"
ATA "LICC LIRF LIML LIMC LIPZ" "ATA Italy"
ATS "C KPDX KRNO KSJC KONT KBUR KPSP KSAN KPHX KCOS KOMA KJAC KSTL KDTW KHOU KMFE KHSV KFLL KRSW KBWI" "_ATS" green
AU "SA" "AUT"
AV "SK SKBO SEGU" AVA
AVP "LF EB EH EHAM EHRD EHBK LFPG LFBD" "_AVP"
AY "EF" "FIN"
AZ "LI" "AZA,SMX,NOV,AZAX" green
BA "EG EGLL EGKK" "BAW,BRT,XMS,SHT,BIS"
BHS "MY" "BHS"
BMA "EG EGLL" "BMA"
BW "M MK MKJP T TT" "BWA"
BWA "MK" "BWA"
BZH "LF LFPO LFLL LFPG" "BZH"
CA "Z" "CCA"
CFG "ED EDDB EDDL EDDH EDDM EDDS" "CFG"
CI "RC" "CAL"
CU "MU"
CX "VH VHHH VTBS" "CPA,AHK,HDA" green
CZ "Z" "CSN"
DGS "K PH" "_DGS"
DL "K KCVG KDTW KATL KJFK KMEM KMSP KSLC" "DAL,DAT,DALX,SNO,DEA"
DNATA "YSSY YMML YPPH YPAD YBBN YPDN EDXB LSGG LSZH OP EGLL EGCC WSSS" DNATA
EFM "EDDM" "_EFM"
EI "EI EIDW EGAA EINN" "EIN"
EK "O" "UAE"
ELAL "LL LLBG" "ELY"
ET "HA HAAB" ETH
EV "K" ExpressJet
EWG "EDDL EDDN EDDH" "EWG"
EZY "EG EGKK EGGW" "EZY"
FFT "K KDEN KMCI KMKE" "FFT"
FQ "EB" "TCW,ARU"
FR "EGSS EIDW LIME EBCI LEAL" "RYR,CYR"
Fraport "EDDF" "_FRA"
G3 "SB SBSP SBEG SBCT SD SI SJ SN SS SW SV" "GLO,AHG"
GA "WI WA WQ WR WIII WADD WAAA WARR WIMM" GIA
GRON "EHGG" "Groundservice Groningen Airport"
GWI "EDDK EDDB EDLW EDDV EDDS" "GWI"
HAL "PH PHNL PHOG" "HAL"
HU "Z ZJHK" "CHH"
IAG "EG LE" "IAG"
IB "LE" "IBE,IBEX"
IG "LI LIEO" ISS
IGO "V VA VE VI VO VABB VIDP VOMM VECC VOBL VOCI VOHS VAAH" IBU
JBU "KJFK KFLL KMCO KBOS KLGB" "JBU"
JJ "SB SBFL SD SI SJ SN SS SW SV" "TAM,TGI"
JL "RT RJAA RJTT RJOO RJBB RJGG RJCC RJFF" "JAL,JLJ,JEX,JAC,JTA,RAC"
JST "Y YSSY YBBN YBCG YBCS YWLM" JST
KE "RK RKSI RKSS RKPK RKPC" "KAL,JNA"
KL "EH EHAM" "KLM,KLMX,KLMC,UKA"
LA "SC SCEL" LAN
LH "ED ET EDDK EDDS EDDB EDDL EDDN EDDH EDDM EDDC" "DLH,DLHX,LHT,CLH,GEC"
LION "WA WI WQ WR WARR WIII" "LNI"
LOSCH "EDDM EDDT EDDS EDLV EDJA" "_LSCH"
LR "MS MSLP MR MROC SP MG MGGT MH MHML" "TAI"
LX "LS" "SWR,SWRX,SWU,CRX"
MENZ "DB FA FAJS FACT FE FG DG OJ GO MD MX TN VM K LK LH LR LE ES EH LIRN Y NZ EG" Menzies
MH "WM WMKK" "MAS"
MK "FI FH FM" "MAU"
MS "HE HECA HEAX HEGN HELX HESH" MSR
NAX "EN ES EK ENBR EKCH ENGM ENTO ENZV ESSA ENVA" NAX
NK "K KDFW KDTW KFLL KLAS KORD" NKS
NZ "N" "ANZ,ANZX"
OA "LG" "OA,OLY"
OS "LO LOWS" "AUA"
PBN "Y YBBN" PBN
QF "Y YSSY YMML YBBN YPAD YPPH YBCS YPDN" "QFA,QFAX,QAC"
RUS "EDDR EDDC" "RUS"
RXA "Y YBTL" RXA
SA "FA FAJS FACT" SAA
SEA "LIML LIMC LIMB" "_SEA"
Servisair "LE LP EG EI EK EF LFPG LFBD EHAM" "_SVS"
SK "EN ES EK ENBR EKCH ENGM ENTO ENZV ESSA ENVA" "SAS,SASX"
SKW "K KSEA" "SKW"
SOGEAAL "LIEA" "_SGE"
SQ "WS WSSS" SIA
SU "U UUEE" "AFL,RCF,DNV"
Swissport "LS EHAM" "_SWP"
TAP "LP" "TAP"
TG "VT VTBS VTCC VTSP" THA
TK "LT LTBA LTAI LTAC LTBJ" THY
TRS "K KBWI KMKE KATL KMCO" "TRS"
TSO "U UUDD" TSO ligthblue
TVF "LF LFPO" "TVF"
UA "K KDEN KLAX KORD KSFO KIAD" "UAL,UALX,UAL,UAC,BLR,UEJ"
US "K KCLT KPHL KPHX" "USA,USAX,ALQ,CHQ"
UVAir "M SB SD SI SJ SN SS SW SV" "_UVA"
VA "YSSY YMML YBBN YPAD YSCB YBCG YMHB YPPH YBTL" "VOZ,VBH,VAU"
VIGGO "EHEH" "VIGGO"
VIR "EGKK EGLL" "VIR"
VO "LO LOWI LOWS" "TYR"
VRD "KSFO" "VRD"
WFS "K LFPO VOCI VTBS" "_WFS"
WN "K KLAS" "SWA"
WS "C CYYC CYYZ CYEG CYWG" WJA
XR "Y YPPH" Skywest
First it's the company ID (it's the folder name of the livery, sometimes it's an ICAO code sometimes it's a IATA code, but it doesn't really matter in this case)
Then, the list of airport ICAO that creates the *scoring* (according to the PaintKit documentation, which explains how the scoring system works)
Then, the code (or codes) that identify the company, which are exactly the same as the one used in AFCAD, OR custom created in case of companies not known to popular AFCAD editors like ADE.