Is it permissible to combine the Dhuhr and Asr prayers after returning home due to obsessive-compulsive disorder (OCD) and uncontrollable flatulence, and the resulting difficulty in performing ablution and praying in front of people at work?

If the flatulence reaches a degree of incontinence such that there is not enough time to perform the prayer with proper purification, then the Hanbali jurists permit combining two prayers. You may combine Dhuhr and Asr if you return home before Maghrib. However, if there is sufficient time for purification and prayer, there is no dispensation for combining, and one must struggle against the whispers of inability to perform ablution and prayer in front of people.