We propose a novel physical model for the attempt-to-escape frequency of trap-to-band electron emission, which is broadly applicable to various trap-to-band scenarios. The model is verified under detrapping mechanisms in bandgap-engineered tunneling oxide (BETOX), enabling accurate prediction of electron emission dynamics within extremely short timeframes. Extensive comparisons between the proposed model and calibrated TCAD simulations demonstrate excellent agreement, validating its accuracy and reliability. Additionally, based on calibrated physical parameters, the model is adaptable to engineering variations such as trap profiles, including intricate combinations of Gaussian trap distributions, making it highly versatile for future device optimization and analysis.