Anything is possible, but without knowing the specifics of his situation it is genuinely impossible to give you a realistic answer. The outcome of a meeting with a probation officer after a violation and transfer depends entirely on details that matter enormously.
The key information that shapes what happens next includes what his original charges were, what the violation was that triggered the hold, how long his original sentence or probation term was, and what his overall record looks like leading up to this point. A first-time technical violation on a nonviolent case looks very different to a PO than a new criminal charge or an absconding situation on top of prior violations.
The month already served in Harris County will count as time served toward whatever comes next, which is at least something working in his favor.
What typically happens at a PO meeting after this kind of situation is one of a few outcomes. The PO reviews the violation and the circumstances, and either recommends reinstatement of supervision with modified conditions, refers the case back to the court for a formal revocation hearing where a judge decides the outcome, or in some cases signs off on a release with stricter terms if the violation was minor enough. The PO has significant influence over which direction this goes but does not always have the final word. A judge may still be involved depending on the severity of the violation.
If you can share more about what he was on probation for and what the violation involved, a much more useful read on the likely outcome is possible.