The escalation rules should be viewed as a shell and starting point, not a rigid checklist. UA looks at the full situation, all factions involved, and all relevant factors before making a determination, including faction size, recent hires, main character status, alt characters, and whether anyone is trying to gain an unfair advantage.
The purpose of a lockdown / hire block is to prevent war jumping, temporary recruiting, and alt abuse. It also makes escalation uncomfortable for everyone involved, which should push factions toward a quicker resolution instead of letting the conflict drag out.
If someone was actively maining a faction but never formally set it as their main, that is ultimately on the player and their faction leadership. If they were involved enough to be impacted by the escalation, they should have seen it coming and made sure their main was properly set. Leadership also has a responsibility to warn members before things reach that point.
A lock can be adjusted or removed if UA believes the specific situation calls for it, but it should not be assumed. Unless UA clearly states otherwise, factions should treat the lockdown and main character requirements as active.
In your case, you were scared because you thought Popov was going to PK you, so you left the faction to do hits for Supreme in another faction. Once you realized there was no orders you left the other faction and now are stuck as a civ. watching from the outside. If you want numbers.....at the start of the escalation Supreme had 140 alts(More than any other crim. faction) to Popov 30 alts, for mains there were 25 for Supreme and 13 for Popov...... this was taken into account during the main lock decision.