Is it permissible to delay congregational prayer until returning home due to the emission of prostatic fluid (imdhâ') and the inability to change the wet clothes outside the home?

It is not a condition for purification from madhy (prostatic fluid) to sprinkle water on trousers and underwear. Rather, istinja (definition)' (washing the private parts) followed by wudu' (ablution) is sufficient. Only the part of the clothing that has been stained by madhy should be sprinkled with water.

Therefore, do not delay joining congregational prayers due to apparent wetness on your clothes, unless you find another congregation to pray with and there is ample time.