New to Texas Hog Hunting.
 

I have already taken two hogs at night with a thermal attachment for my scope. Works out really well. That was in January of this year. But now, I haven't seen hide nor hair of any sitting out till 2200, or 10:00 PM.

First question, do I need to sit longer? My first two were taken before 2000, or 8:00 PM. Now I have seen none in over a month. I have used sour corn, pig oil, attractant scents, sow urine, but nothing after sun goes down. What does show is between 5 and 8 raccoons or more.

That is the second question, research says hogs will follow raccoons to food, then run them off. However, does this many of them keep the hogs at bay because they don't want the hassle? The raccoons just take over the feeder after dark.

I am looking and open to any advice from Hog Hunters and especially hog hunters from Texas, or also might hunt the Texas Hill Country for pigs.

I never hunted hogs in Texas but I did in Georgia and I still do in SC, I wouldn;t worry about racoons, even a small hog can kill a coon. Hogs travel around looking for food and they are not always in the same place at the time. If you can get permission on the property you hunt ask permission to put some feeders out and keep them filled with corn. When the hogs find the food and get used to finding corn when the feeders go off they will hear it and come running byt they have to know food is usually available.

As a "Texican" and adopted "Okie" with "some" hog experience.
In my experience, when you shoot up a "sounder" (a group/herd) of hogs, they either go nocturnal OR leave that area.
Nature hates a vacuum, another sounder will replace them, but it may not be overnight!
When we trapped hogs in southern OK, we had to move the trap when we caught hogs.
Feral hogs ain't stupid and the will get trap wise.

You're not doing anything wrong. Take a break for a week or so. More will eventually show up.