Nothing in the regs re asymmetric training/checking in imc/night. What you see/experience in your training is the procedures being followed as per an organisations 'SOPs' (these directives come under many acronym) and thus the development of an 'off the shelf' training program with a usually heavy emphasis on day ops.
Re night time - this may limit asymmetric simulation to not be carried out below an certain altitude/condition(imc)/environment, which then prevents the opportunity to train/practice the EFATO/missed approach.
Any training at night presents an excellent opportunity to experience so many night related stressors, that as a customer you could hopefully sit down and discuss and see what they could offer you. Some syllabus are approved and cannot be changed (self sponsored Q cadets) - but this may not be your case.
