Can a friend fulfill the Rosh Hashanah Musaf prayer obligation for someone who did not pray?

Synopsis

A friend cannot fulfill (be motzi) another's obligation to pray the nine blessings of the Rosh Hashanah Musaf prayer, though they may fulfill other obligations like shofar-blowing through proxy.

Early Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

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