It was like a lightning ... actually quite many of them but finally i got new Guardian friend.
During the treasure hunt i noticed that some types of the Guardian mobs are having tag 'tameable' so i decided to check it out ... and the outcome is :

What did i test :
* first of all if it will de-spawn after treasure chest will be gone (bye bye chest) :

Nope he decided to stay ... so i felt quite generous and offered him a Sov based juice :

And yes it bonded pretty nicely :

Checked if he will de-spawn after getting killed (hint, no he actually liked sov juice so much) :

Maybe there was some timer ? Waited ~24h ... and he is still here, with me ...

Some additional notes :
* excluding (Guardian) tag that is staying even after rename ... it is a normal pet this one is actually pretty weak.
* this is just Guardian .... that is spawned when the chest is showing up, not the OP mob that is showing when you fail the disarm trap.
* after taming guardian, chest cannot be lockpicked until it will die - stabled, dead, logged out ... no matter, game knows it is some where alive.
* i was doing this in the Tokuno, thus pet types, will check out Tram map as i have a Trove there.
Bonus note :
When you open the chest similar coloured pet can spawn, but without the Guardian tag, rarely but it happens :

During the treasure hunt i noticed that some types of the Guardian mobs are having tag 'tameable' so i decided to check it out ... and the outcome is :

What did i test :
* first of all if it will de-spawn after treasure chest will be gone (bye bye chest) :

Nope he decided to stay ... so i felt quite generous and offered him a Sov based juice :
And yes it bonded pretty nicely :

Checked if he will de-spawn after getting killed (hint, no he actually liked sov juice so much) :

Maybe there was some timer ? Waited ~24h ... and he is still here, with me ...

Some additional notes :
* excluding (Guardian) tag that is staying even after rename ... it is a normal pet this one is actually pretty weak.
* this is just Guardian .... that is spawned when the chest is showing up, not the OP mob that is showing when you fail the disarm trap.
* after taming guardian, chest cannot be lockpicked until it will die - stabled, dead, logged out ... no matter, game knows it is some where alive.
* i was doing this in the Tokuno, thus pet types, will check out Tram map as i have a Trove there.
Bonus note :
When you open the chest similar coloured pet can spawn, but without the Guardian tag, rarely but it happens :
