I realize this is a year-old topic at this point, but I wanted to bring it up in hopes of a possible solution that happened in the meantime.
We just launched our Magento 2.2 shop, and this comment field that used to go into Payflow is no longer making it through. The owners of the shop use this comment field for reconciling payments and needing to cross reference it between Payflow and Magento is not an option - it needs to go into Payflow as "comment1".
Has anyone else had a similar issue or is there a location I can go to change the name of the field in Magento? Please advise.