Is it obligatory to repeat prayers after the emission of a viscous fluid other than pre-seminal or seminal fluid, and does opening the glans of the penis to ensure nothing has exited nullify ablution?

You may be afflicted with waswasa (obsessive whispers); if so, ignore them and turn away from them. The fluid that exits you is either madhi (pre-seminal fluid) or wadi (a thick white fluid that may be discharged after urination), and both are najis (impure). You must wash the private parts and any part of the body and clothes that it has touched, then perform wudu' (ablution) for prayer. Do not search for its exit; when you see it, perform istinja' (washing the private parts) and wudu'. If you doubt the time of its exit, estimate its exit at the latest possible time. Istinja' is not required for it unless it appears on the outside of the private parts. Touching the private parts with a barrier does not invalidate wudu'.