First of all, posting identifying information in a public forum such as this is unwise. To make defamatory comments about a specific entity is especially foolhardy. Contact Avvo customer service promptly to edit your post.
The agency that may take your complaint is the Consumer Affairs (or similarly names) division of your state's Attorney General.
This answer is offered as a public service for general information only and may not be relied upon as legal advice.
First thing to ascertain is where the charity is based. Once you have done that, you can contact that state's Attorney General (the AG's office usually has oversight responsibility over charities operating in their state). You can also file a complaint with the IRS utilizing Form 13903. Finally, you can have someone with expertise in EO Law review the Form 990 for the entity to see if they identify anything.
Seems to be a non profit but not necessarily a 501(c)(3) charity - treat it the same way you would any business that you believe is engaging in unethical practices.
This is not legal advice but a general comment on society based on a limited set of hypothetical circumstances. No one should act or refrain from acting based on these comments without seeking appropriately licensed legal or professional advice. The author disclaims all liability in respect to actions taken or not taken based on his comments.