There's no way Veer can die so soon. Looks like blood donation will be the way for Veer to come to know the truth.
Blood donation from jai is highly impossible as jai has BP and diabeties from past 30+ years, even before he got married to bani.
I know i am being stupid to even comment on this , In ekta's world even BP patients can donate blood.
So won't be surprised if it happens.