You can do the double meta refresh with a check and then send to the offer...

If they question you about the blank referrer... Tell them you do PPC and you run all the traffic through your tracking system.

High Volume - When you get the "shits and giggles" because you are making a ton of coin.
Low Volume - When you walk around the house aimlessly thinking "Daaaamnn... I need to make more money".

Seriously... You probably should switch up CPA Networks / Offers... Rotate the traffic so it's not all going to one Network / Offer.

Hope that helps...