Sevagoth Exalted Shadow: Railjack mission termination

[CxLL]

Gara Prime: Hotfix 30.3.1
Ticket number:  #2521241

Activating the Exalted Shadow ability on Sevagoth while invading either an enemy or a derelict vessel will push Sevagoth into a state between the two forms. During this state
- All abilities are marked as "in use", making them unusable (this applies to transference)
- Melee cannot be used
- Interaction with the environment is disabled
- Warframe invisible to enemies
- Secondary weapon can be used but not reloaded
The enemies will keep targeting the equipped companion which may result in a lockdown. Terminals cannot be interacted with, therefore no exit is possible. 
In case of an exit being available, it is possible to interact with, however, the warframe will be teleported outside of the map.
- Flying towards the map is possible but slower than normal
- Blinking forward is disabled
- Archwing abilities work, passive doesn't
- Gear is disabled
- Taking a (very) long time to fly will trigger evacuation ("ship departing, get back on board"), which will eventually teleport the warframe into their ship and end the mission by returning to the dojo
- Exiting to dojo via Esc menu will result in the same outcome.

Should this occur during the main mission, before the objective has been completed, the mission will be marked as failed.
In case of it happening after the mission objective has been completed (as in a derelict vessel visited once all tasks have been filled), returning to the dojo will have the mission successfully completed.

Steps of reproduction

1.  Have no primary equipped
2.  Enter vessel
3.  Fill Death Well
4.  Press 4

Not tested:
- in a squad
- with a primary equipped
- reviving (in lack of sources of damage)
- using the Liset auxiliary to bypass a lockdown

Tested in:
- EARTH PROXIMA
Ogal Cluster
Korm's belt

- VENUS PROXIMA
Beacon Shield Ring
Orvin-Haarc
Vesper Strait

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Arsenal equipment used:
Warframe: Sevagoth (17->18 and 30)
Primary: None
Secondary: Epitaph (29->30)
Melee: Lesion (30), Caustacyst (30), Kronen Prime (30)
Sevagoth's Shadow (max rank)
Shadow Claws (max rank)
Companion: Sly Vulpaphyla (11), Helios (30)
Archwing: Amesha (unranked)
Archwing primary: Phaedra (30)
Archwing melee: Agkuza (30)

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Additional information:

- Solo mode (rather than squadless)
- Three npc crew members on railjack ship
- Borderless window mode
- DirectX 12 (Beta)

This issue is of a recurring nature and has been happening for a very long time now, although the causes for it have been different. 
A number of threads are referring to identical symptoms, largest thread among them would be
https://forums.warframe.com/topic/906444-ability-in-use-bug-disables-all-abilities-transference-and-more/

- - - -

Further testing required.
Requested:

- with primary equipped
- in squad
- possibility of dying once the issue occurs

Please reply to this thread with your findings, thank you.