There's nothing wrong with ending the show at a point before Pike's time commanding the Enterprise comes to an end. So Pike continues to have adventures which simply won't be televised. It'll help the tie-in material continue to do SNW stuff without being constricted to fitting it within the timeframe of the series, and it leaves the door open for potentially revisiting the show at some point, like a streaming movie assuming Section 31 didn't completely soil the concept irreparably.
And really, the epilogue scene tying into Calypso was completely unnecessary in Disco's finale, that scene between Michael and Book on the beach worked perfectly as a final scene anyway. Seeing Pike's fate in SNW's finale would be just as unnecessary, maybe even more so given we already saw his accident on Disco, with footage of it already having been shown on SNW a few times in S1.