The Czech star's side, Chelmsford Chieftains, needed to overturn a 6-3 scoreline from the first leg.
But Invicta Dynamos further compounded the result by winning 3-1; 9-4 on aggregate.
Cech switched football for ice hockey shortly after retiring in 2019 when he signed for Guildford Phoenix.
The four-time Premier League Golden Glove winner joined the Chieftains in November.