What a mess. I'm not even sure what you're trying to accomplish. Besides, you're not trying to reword a room rental agreement. That apparently was signed December 22. You can't reword a signed agreement.
Tip: In situations like this, just write in ordinary English. You're not a lawyer, you don't know lawyer jargon, and you're just getting all tripped up and confused.
Disclaimer: I'm not a lawyer, so this isn't legal advice. For that, you need a lawyer. However . . .
It sounds as if you're trying to say the December 22 agreement is void because the tenant didn't pay the $200 deposit. If so, are you trying to collect the $200 from him? Or are you tossing him out because he hasn't paid and therefore the tenant hasn't complied with the written agreement? Or are you letting him stay without paying?
Just keep it simple. If it's a notice, write:
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The room rental agreement signed on December 22, 2014 by [landlord's namename], landlord, and by [tenant's name] tenant is void because [tenant's name] failed to pay the required $200 security and cleaning deposit.
~~~~~~~~~~~~~~
If you're amending the agreement to say that the tenant can rent without paying the security deposit, use the following language:
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Landlord, [landlord's name], hereby amends the room rental agreement signed by [landlord's name] and by [tenant's name], tenant, on December 22, 2014, to remove the requirement for payment of a $200 security and cleaning deposit. All other provisions of the December 22, 2014, agreement remain in force.
~~~~~~~~~~~~~~~
With this language, both you and the tenant should sign.