It's very disappointing that they used metal shielded bearings in that application where water and moisture are in the environment around them. That is "asking for" failures. You made a great choice in buying rubber sealed bearings.
Metal shielded bearings do have a place; typically in places where the temperature may be too high for rubber seals, or in areas where the bearing runs in oil or is connected to an external grease supply, which can pass around the shield but larger particles cannot.
Using these in an open and wet environment is just asking for a short life and many failures.
EDIT: Watching the video was informative but seeing the badly bent shield on the NEW bearing going in was very disappointing!
Comes to the Rescue!
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