I'm not sure why we are seriously considering Boras's opinion on this. Would Boras say anything else? He's an agent. It's his job to talk up his clients. The choice to bring up Meyer now or next spring has nothing to do with cash at this point, as the Twins won't gain any advantage unless they bring him up next July. And earning his favor is pointless.
Players hire Boras b/c they know he can get top dollar, and his clients want that. But at the end of the day, Boras doesn't make the call, Meyer does. If the Twins are concerned about anyone, it should be Alex Meyer, b/c if this leaves a bitter taste in his mouth, there will be no extension when the time comes. This tends to be true with Boras clients in general I might add (not as much with Pitchers) as his clients tend to want top dollar.
It's on the Twins to make sure they have clearly communicated what they are wanting from him and what it takes to get there. If Meyer bolts after his 6 years, I highly doubt this will be why... Just my 2 cents.