Hi James, welcome. I am a licensed attorney and happy to assist.
Since the surety bond payments are rightfully owed, you can't automatically reduce or remove the bond payment. That said, you are under no legal obligation to have any documents notarized unless the original contract you signed requires you to "take any action in furtherance of effectuating the agreement, as requested by the bondholder." Absent some sort of language to that effect, notarization would not be required, but the legal effect would be the same, either way. If the company was to later take legal action for non-payment, they would be able to prove validity of the debt, with or without notarization.
Lack of original notarization does not void the contract because the bond company fully performed its side of the bargain by providing the bond when needed. I wish I could tell you otherwise, but having accurate information allows you to make informed decisions going forward.
I hope this helps. If you need additional information or clarification, just let me know and I'll be happy to continue providing assistance. If you still feel a phone discussion would be helpful, just let me know I will submit an additional services offer for that purpose.
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