Ant infestation: do I need to replace siding/wall
With the carpenter ants you may need professional help. I have had to do some extensive repair work in the Pacific Northwest for carpenter ant damage I would be examining the area you have identified as an entry and several stud bays on either side. You may be lucky and they may not have harmed the structure , and siding / Trim. In 1 case I had to replace about 10’ of exterior wall that was only holding in place with the sheeting. I don’t mess with these guys because if you don’t kill them they move to another wall and start chewing it up. After several houses I started biting the bullet when I found them and removing the Sheetrock / lath and plaster having that area sprayed with some stuff only chemical applicators can get, also the inside and outside areas of the foundation. After that I never had a reoccurrence. It really depends on how bad the damage is if it all needs to be replaced but if you are seeing any kind of dust , bodies they can be hollowing out the studs until there is nothing left. If the wood is stable it may be ok to leave alone but I would get some pro help, the stuff they can put on the exterior of the foundation and at the base of the siding can last 10 years, plan to re do it if you have had problems or you may find a wall gone we just got lucky in one case it was found on the inspection.