Yeah, sounds like Gollbach was out of the area quite some time before Howard met him in Rio Grande City. I suppose it's possible they met when the Howards lived in Burkett, not too far from Coleman, 1918-19, but I doubt it. And REH would only have been 12-13.
Gollbach was born in Germany in 1878 and moved to Texas shortly after being ordained in 1906. I've got him listed on a "Manifest of Alien Passengers" arriving in Galveston in December 1906. His destination from there was a seminary in San Antonio (where he died in 1955). The 1930 Census has him in Rio Grande City. I haven't found him on an earlier Census, but his 1918 draft registration has him living in Ballinger, Runnels County. A Texas Historical Marker has this:
A native of Germany, Gustav Gollbach was ordained a priest in the Oblates of Mary Immaculate Order on April 21, 1906. He immigrated to Texas soon after his ordination, and served churches in Del Rio, Castroville, Mercedes, San Benito, and Ballinger before coming to Rio Grande City in 1924. Serving as pastor of Immaculate Conception Church until 1937, he built a replica of the Grotto Shrine at Lourdes, France, using petrified wood and native stone from the Roma area. Dedicated in 1928, it has become an important historic site in the Rio Grande Valley.
I've found several references to border crossings in the 1930s, as well as numerous articles in South Texas newspapers. No mention anywhere of him being in Coleman. Where does that information come from? If he was serving there, seems like it would have been before landing in Rio Grande City (1924) or after his stint at Immaculate Conception Church (1937), which would have been too early or late for REH to have noticed.
There's always something in the works; I just don't like saying what it is until it's almost ready. That way, no one gets irritated when things are inevitably delayed. Having said that, there's autobiographical fiction, humorous westerns, and a bunch of stray stories that still need a fresh coat of paint.