The above hadiths don't say anything about Karbala since they are Sunni hadiths. Shias have their own hadiths in which the Prophet predicts about Karbala, but that's a different topic altogether.
But you are right in one respect, hadiths were made up centuries after the Prophet's death, they each should be taken with a truckload of salt.
Sahih hadith from Buhkari,Muslim Abu dawud etc have been thoroughly tried and tested for 1400 years by the best scholars! So they have done the job for us in regards to confirming authenticity of these Hadith! These hadith have chains of narrations that are unimaginably long! Thats what makes them so authentic! I would recommend that people actually study the science of hadith in order to understand rather than just make opinions up with limited knowledge!