Good post, Jake. I like your free-agent qb metaphor for Leron. So when I think of which company needs us more, I go back to football history. Merck might be like the Chiefs -- or the Packers -- a few years ago. Merck has their SOC drug; in terms of market, it's like Aaron Rodgers was for the Pack, but in terms of capabilities, it's more like Alex Smith. So you draft a young quarterback (Jordan Love, Pat Mahomes), not for right now, but for the future; you run a combo trial, so with luck you can turn to Leron when Keytruda's playing days are over. So which scenario plays out? You find out Mahomes/Leron is better than Smith/Keytruda, and turn quite quickly to the young qb/drug; or you're not sure, so you hang onto Rodgers/Keytruda for as long as you can, and Leron rides the bench, while you develop the market for it.
Then there's Bayer. Their qb is barely better than the average replacement player. Imagine you were the Bucs of a few years ago, with Jameis Winston at qb. You need a free agent qb now. More expensive than the draft choice, but reaps faster rewards. You have to pay Tom Brady. But it's worth it.
Now that I've clouded the idea with my extended metaphor (just trying to be like Plotinus or MGK), I can say I think Leron might be worth more to Bayer right now. Until Keytruda reaches retirement age.