[confirmed]Bestow vs. Can't Cast

[Korath]

Describe the Bug:

1. Sanctum Prelate prevents creatures with bestow and the chosen cmc from being cast, whether as creatures or auras.
2. Steel Golem and similarly-worded cards prevent creatures with bestow from being cast, whether as creatures or auras.

I can't decide whether these are separate bugs, or related bugs, or just different examples of the same one.

Which card behaved improperly?
Bestow's fault, or the approximation used for can't-cast, or maybe both. But not the individual cards' fault.

Which update are you using? (date, name)Which type? (duel, gauntlet, sealed deck)
Dev e9d990e.

What exactly should be the correct behavior/interaction?
702.102c The check for whether a spell can legally be cast happens after its controller has chosen whether to pay its bestow cost; see rule 601.2e.
Example: Aether Storm is an enchantment with the ability "Creature spells can't be cast." This effect doesn't stop a creature card with bestow from being cast for its bestow cost because the spell is an Aura enchantment spell, not an enchantment creature spell, when the game checks whether the spell is illegal.

Are any other cards possibly affected by this bug?
I'll admit surprise that Gaddock Teeg works correctly with high-cmc bestow cards like Celestial Archon - it lets you cast them only as creatures.

Related.

[Aswan jaguar]

Confirmed for Steel Golem, and the similar worded Grid Monitor, and Brand of Ill Omen.I can't confirm Sanctum Prelate as it doesn't exist in public version.