thanks ven of that tip, worked for me too (collisions broke during diplomatic immunity, I guess cause was some of these: dephine took few mod added quest related items into chest, fast travel was disabled in frostfall, glitching revered dragon attacked embassy when arrived there (it was stuck outside keeping guards and stewards busy till they slayed it:D),bolag mals inferno adds oblivion gate near embassy, fight against thalmor part 1 is close by, AFT could have caused follower script error even thouhg I parked them into solotude before starting quest, convient horss could have had also script error on arrival) and apparently made this part way too easy as enemies were stuck too