Errantry vs attack if able

[Aswan jaguar]

Describe the Bug:
Errantry at least for AI can affect other cards than the enchanted card. AI cast it on Brood Keeper but could bypass Juggernaut 's ability and not attack with Juggernaut as AI had to it didn't attack with Brood Keeper either. Besides Errantry shouldn't make Juggernaut not attack even if it enchanted it.

Which card did behave improperly?
Errantry? attack if able code?

Which update are you using? (date, name)Which type? (duel, gauntlet, sealed deck)
Manalink dev 778ccb5 version - duel

What exactly should be the correct behavior/interaction?
Errantry affects only the enchanted creature to attack alone and you can't choose to do that if you have a creature that must attack if able.
I don't think this is this case:
4/27/2018 If Juggernaut can’t attack for any reason (such as being tapped or having come under that player’s control that turn), then it doesn’t attack. If there’s a cost associated with having it attack, its controller isn’t forced to pay that cost, so it doesn’t have to attack in that case either.
Are any other cards possibly affected by this bug?
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