Matching Gifts - especially when not notified of them (NEW Tess user)

My organization is often on the receiving end of matching gifts. I've just moved from RE to Tessitura in the last couple of months, and I'm finding very difficult to manage this process.

At this point, I've done the following per the help system:

1. Set up the company as a new corporate constituent

2. Added the necessary attributes (ratio and schedule)

3. Added the affiliation between the donor and the company

I already have the original gift on file from roughly a month ago - I did not know this donor was setting up a 1:1 match for us, and so now that we've gotten the check from the Charities Aid Foundation America on behalf her company, I am unsure how to proceed - do I need to submit an adjustment to the original in order to produce the pledge that would be paid off by this check, or should I simply process the gift another way?