Cannot install required cocoapods plugin

Simple problem: Cannot install required plugin

$ pod install

[!] Your Podfile requires that the plugin `cocoapods-keys` be installed. Please install it and try installation again.

Podfile::

plugin 'cocoapods-keys', {
  :keys => [
    "GitHubAPIClientId",
    "GitHubAPIClientSecret",
    "BitBucketAPIClientId",
    "BitBucketAPIClientSecret",
    "BitBucketEnterpriseUsername",
    "BitBucketEnterprisePassword"
]}

source 'https://github.com/CocoaPods/Specs.git'
source 'https://github.com/czechboy0/Podspecs.git'

project 'Buildasaur', 'Testing' => :debug

platform :osx, '10.11'
use_frameworks!
inhibit_all_warnings!

def pods_for_errbody
    pod 'BuildaUtils', '~> 0.2.7'
end

def rac
    pod 'ReactiveCocoa', '~> 4.0.1'
end

def also_xcode_pods
    pods_for_errbody
    pod 'XcodeServerSDK', '~> 0.5.7'
    pod 'ekgclient', '~> 0.3.2'
end

def buildasaur_app_pods
    also_xcode_pods
    rac
    pod 'Ji', '~> 1.2.0'
    pod 'CryptoSwift'
    pod 'Sparkle'
    pod 'KeychainAccess'
end

def test_pods
    pod 'Nimble', :git => "https://github.com/Quick/Nimble.git", :commit => "1730543fcd8b7d7258a3270bb6d3118921d46f9d"
    pod 'DVR', '~> 0.2.1-snap1'
end

target 'Buildasaur' do
    buildasaur_app_pods
    pod 'Crashlytics'
    pod 'OAuthSwift'
end

target 'BuildaKit' do
    buildasaur_app_pods
end

target 'BuildaKitTests' do
    buildasaur_app_pods
    test_pods
end

target 'BuildaGitServer' do
    pods_for_errbody
    rac
end

target 'BuildaGitServerTests' do
    pods_for_errbody
    rac
    test_pods
end

target 'BuildaHeartbeatKit' do
    also_xcode_pods
end

$ pod plugins install keys

Installing plugins: keys
[!] /Users/ndgbuild/Downloads/CocoaPods.app/Contents/Resources/bundle/bin/gem install --no-document --env-shebang --file /var/folders/x9/fs3mfz0n2992hxwc1n87741c0000gr/T/cocoapods-plugins-install-keys20160608-83341-2plqwf

ERROR:  While executing gem ... (Gem::UnsatisfiableDependencyError)
    Unable to resolve dependency: user requested 'io-console (= 0.4.3)'

The specified dependency is for the cocoapods-keys plugin, which specified that one version which is not available in any gem repository. I realize that this may not be a problem specific to the app, but I was able to get this to work once a few weeks ago using a beta version of the app. I have the plugin installed on one mac, and am trying to get it to work on a new mac.

If one does a 'pod plugins' commmand, it displays a list including cocoapods-keys. If no one can install the plugin, it shouldn't be in the list of plugins.

CocoaPods / CocoaPods-app

Cannot install required cocoapods plugin #346