I have tried to reproduce this with the following deck
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52i 52i 52i 52i 52i 52i 5v0 5v0 5v0 5v0 5v0 6u3 6u3 6u3 6u3 6u3 6u3 6ve 6ve 6ve 6ve 6ve 6ve 7an 7an 7an 7qb 7qb 80h 80h 8pk
The idea was to manually poison, epinephrine (to kill the singularity) and then quint it, playing a Voodoo Doll right after. Apparently this can't be reproduced manually, so I guess it's completely by chance getting the Epi'd --> Quint (and being poisoned while at it) singularity to confirm this bug. :/