found out recently that cutscene triggered alarms does not fail the elite challenge requirements 'do not get detected'.
this only applies to opening the main door via explosives or landing the velum plane without weapon stashed.

this one was without any disruption preps or cutting powder done, embarrassingly took me quite a lot more hours than imagined, due to the overpower aimbot guards firing minigun rounds at me around every corners
got properly scared in the end and went for the very lame swimming exit.
also missed a combat shotgun at 04:50 mega cringe big fail