Is it permissible for a Muslim to offer the Fajr (Dawn) Prayer in congregation after having made Tayammum (dry ablution) due to a wet dream or Janabah (major ritual impurity). The reason behind performing Tayammum instead of Ghusl is that the Imam of the Masjid (mosque) may hasten pronouncing Iqamah (call to start the Prayer) before Ghusl is performed.
A Muslim should perform Ghusl (ritual bath) and Wudu' (ablution) for Salah even if they are afraid of missing the congregational Salah. It is not permissible for them to perform Tayammum if they fear that by performing Ghusl, they will miss the congregational Salah. (Part No. 6; Page No. 197) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.