Synthesis target: vanished/unspawned?

[desmerit]

I was doing my weekly maroo quest and it was on an infested derelict.  The infested troops were already present (prior to retrieving statue) and simaris told me my target (runner) was there.  The Juggernaut announced its presence and I ignored him as usual and just kept going forward. I was on [nezha] and had warding halo active (and it was killing the low level infested). Right as I located my synthesis target the juggernaut howled in protest.  My target (with me in fast pursuit) ran past the juggernaut (which i casually ignored) and went through a door and then just instantly vanished and my tracker on the mini-map was gone.  I thought, "oh, he went invisible" so i waited...and waited.  There was no animation of smoke or anything like one normally sees when the target stealth's, and it didn't re-appear. I'm running under the assumption that due to the juggernaut spawning the target executed the "i got away" protocol and was removed from the map.  Simaris never said "you let it get away >:( " or anything though so I'm quite confused.

warframe: Nezha

location: maroo ayatan - infested derelict

special condition: juggernaut spawn

Bug/Error: Synthesis target disappears/ no-longer on map