A poisoned-well "argument" has the following form:
1. Unfavorable information (be it true or false) about person A is presented by another. (e.g. "Before you listen to my opponent, may I remind you that he has been in jail")
2. Therefore, the claims made by person A will be false.
I didn't make any assumptions on the veracity of their data or claims. Think tanks are politically motivated groups whose work entirely revolves around shifting the public's and decision makers opinions. I don't think it hurts to add a disclaimer.