I suspect that this set back was discussed in detail and agreed with the Program Manager. Not a surprise, but a disappointment.
One would have thought that with the years of putting these things together and the known pitfalls in design, and as noted above, the recent experience with S-92, this design effort over the past few years would not have been caught out.
Then again, the entirety of helicopter design involves tradeoffs and compromises, and nowadays a bit of risk. Sometimes, that risk shows up in a "no, it won't work out" result.
Press on, team, and grind it out. (Wait, maybe not the best choice of words for a transmission issue.
)