You should be good. Tomatoes are surprisingly tough plants, so with with root system intact they'll snap right back. A couple years ago, I had a hornworm eat through 90% of the stalk on a huge Amish Paste plant. I duct-taped a strip of old t-shirt around the wound and to try to keep moisture in and moving up the stem. I didn't really expect it to work, but the plant continues producing as if nothing had ever happened to it.
HOWEVER...this year I have a squirrel who refuses to take the hint that it's not wanted. Doesn't care about my dog, does care some when I put cayenne down, but it returns as soon as the cayenne gets washed away. This is the first time I've dealt with a persistent squirrel in my tomatoes, and I'm fantasizing about putting it six feet under. Honestly...if I lived out in the country I'd have purchased an air rifle by now to off this thing.