Why do crooks rob banks? Because that's where the money is. Therefore, it seems to me that Univision should hire a proficient engineer and look into moving the station into the Houston market.
It's not a matter of poor engineering or bad consulting, it's the FCC's own spacing rules (73.207).
In the case of KQBU-FM 93.3, which is a Class C FM, two of the primary obstacles to getting closer to Houston are KKBQ 92.9 and KQBT 93.7. Both of those are second-adjacent (two channels away) and Class C stations. Both 92.9 and 93.7 broadcast from Missouri City, but KQBU is slightly further east.
What is the FCC's spacing rule regarding a second-adjacent Class C to Class C? 65 Miles. How far is KQBU-FM's Devers tower to KQBT? 66 miles. It's practically as close as it can be barring a major rule change from the FCC.