Most Accurate Conversion Tracking Software?

I've been trying to track email conversions via Act-On forms and verifying with Google Analytics thank you page but as you can imagine - one of the problems is our own testing (I've excluded IP addresses in filters). Is there any program that could track this?

Not sure to understand your question since you did manage to track the conversions as well as excluding your IP addresses.
If you're looking for a tracking software - that specifically offers these type of services without the complexity of google analytics - then you have plenty of choice, including TrackingDesk.