Sorry for the delay Dorsey and thanks for the extra information.

I have looked quite a bit in Cass County but was not able to find Mathew, I belive he is not listed in 1900. I have not looked as much in 1910. I also think your research has shown that he should be in Cass County in both 1900 and 1910.

In 1900 there is one couple that I would look in to more:
Just above the household of A. W. and Jane Warren (precinct# 3, enumeration district 24, page# 8A) there is a couple Mat and Mary Barner that are recently married. To me it looks like he belongs to the household further up (Callie Barner + children) and would therefore not be your Mathew, but I was not able to find a marriage for a Mat Barner on familysearch.org Texas marriage database.

If Mat Barner is not your Mat, then you probably have to accept that Mathew for whatever reason is not listed in 1900. In 1910 I did not look at all possibilities, I leave that for the more seasoned veterans on this board

Thanks & good luck!
Johan