Ruby, 6057 bytes
f=->t,a{a!=t&&t!=0&&t=t&&t&&t.zip(a).map{|r|[f][t.size^a.size][*r]}}
Uses nil as filler. (false will also work)
Ports @pxeger's Python answer.
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Visit Stack Exchangef=->t,a{a!=t&&t!=0&&t=t&&t&&t.zip(a).map{|r|[f][t.size^a.size][*r]}}
Uses nil as filler. (false will also work)
Ports @pxeger's Python answer.