Plain words with multiple translations:
EXCEPT: NEH-DIH, NA-WOL-NE
HIGH: WO-TAH, EXPLOSIVE
SUPPLY: NAL-YEH-HI, SHIP
TANK: CHAY-DA-GAHI, DESTROYER

Code words with multiple translations:
AH-DEEL-TAHI: DEMOLITION, DETONATOR
ALI-KHI-HO-NE-OHA: ELEVATE, TERRACE
ALTH-AH-A-TEH: CLASS, TYPE
BIH-TSE-DIH: BEFORE, PREVIOUS
BILH: CONSIST, WITH
BOSH-KEESH: SHORT, SIDE
CHA-GEE: THE, THEY
CLO-DIH: FIELD, OUT
IL-DAY: ARRIVE, REACH
KUT: NOW, PRESENT, READY
NAHL-KIHD: CALIBER, DEGREE
NAZ-PAS: ROUND, SURROUND
NEH-DIH: BUT, EXCEPT
SHIL-LOH: EXPEDITE, IMMEDIATELY, QUICK
SHIP: MERCHANT, SUPPLY
TA-A-TAH: ALL, ENTIRE
TAH-BAHN: BEACH, SHORE
WHO-NEH: REPORT, REVEAL
WO-CHI: FLARE, ILLUMINATE
##</code><code>##

my @words = split /\s+/, $str;
foreach my $word (@words) {
    $word = $CDICT{$word}, next if exists $CDICT{$word};

    my @letters = split //, $word;
    foreach (@letters) {
        next if /\d/;
        if (exists $CALPHA{$_}) {
            $_ = $CALPHA{$_}->[ rand @{$CALPHA{$_}} ];
        } else {
            croak "Letter '$_' not found in encryption dictionary";
        }
    }
    $word = join ' ' => @letters;
}
return join '  ' => @words;