Gable end fink truss repair of bottom chord

[RESCFL LLC]

I have a 1993 home in Florida and found that the gable end fink truss has a rotten bottom chord of about 2 feet from either an old water leak or possibly termites. The house is stucco on the outside. My only option for repair would be to sister it from the attic side with an 8' length of 2x4 with 3-inch GRK construction screws in a zigzag pattern like a girder beam. Of course, I cannot sister both sides because of the stucco and gable end. Since it is a gable end fink truss and it is fully supported by a masonry block wall, would this be an appropriate repair? I am a licensed Certified residential contractor(CRC) in Florida. I do not see any other options to repair this. 2 pictures included. Tight working spot in the attic.

 

[KootK]

I find it difficult to tell just what's going on from the photos but, at first blush, I doubt that any repair to the bottom chord is necessary for this short of cleaning it up and addressing the potential for future rot.

I'd recommend having a local P.Eng come out to review the situation for good measure.