I have a deck and I have noticed that the Discover mechanic does the same bug. If the card that it target has multiple ways to cast the card it just asks a question if I want to resolve with a singular option to resolve. Clicking the resolve button results into putting the card into hand.
I run things like Push//Pull and it won’t cast the card.

Deck
4 Trumpeting Carnosaur (LCI) 171
4 Bloomvine Regent (TDM) 136
4 Breaching Dragonstorm (TDM) 101
4 Disruptive Stormbrood (TDM) 178
4 Bramble Familiar (WOE) 164
4 Decadent Dragon (WOE) 223
4 Vaultborn Tyrant (BIG) 20
2 Raucous Theater (MKM) 266
4 Fabled Passage (BLB) 252
2 Underground Mortuary (MKM) 271
2 Thornspire Verge (DSK) 270
4 Forest (FIN) 306
2 Swamp (FIN) 300
2 Mountain (FIN) 303
4 Stomping Ground (RNA) 259
4 Kona, Rescue Beastie (DSK) 187
1 Kavaron, Memorial World (EOE) 255
2 Evendo, Waking Haven (EOE) 253
1 Susur Secundi, Void Altar (EOE) 259
2 Ghalta, Stampede Tyrant (LCI) 185

Sideboard
4 Push // Pull (MKM) 250
3 Cease // Desist (MKM) 246
3 Virtue of Persistence (WOE) 115
3 Scavenger Regent (TDM) 90
2 Deadly Cover-Up (MKM) 83

Same. Breaching Dragonstorm does not let to cast the spell after it activates

It also happens when Trumpeting Carnosaur enters play through Random Enconteur or Smugler's Surprise and discovers into Bloomvine Regent. Don't click resolve or regent will go into your hand, instead click the exile zone and choose the mode you want to cast.

Mine has been doing this too. If it hits other cards it gives the option to play them but when it hits the Bloomvine it doesn't give the option to choose which half of the card to play. The only option it shows me is to resolve which puts the card into hand. I came here to report this bug and I am glad to see you did.
It has been doing this at least a week.