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I'm sorry to hear about your situation. No, they cannot. A jurisdiction pursuing child support cannot freeze a corporate bank account (assuming that it's not in the name of the individual). It can only go after the individual's bank account, assets, etc... They can get a "charging order", meaning that payouts to him would be garnished prior to making it to his bank account, etc... but they can't actually levy / attach / garnish the corporate account.
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