You need to make sure those addresses you are trying to ping are encapsulated over the tunnel or else you will get translation failures.
Can you provide your tunnel traffic ACLs?
The error you describe has the following description:
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Explanation A protocol (UDP, TCP, or ICMP) failed to create a translation through the firewall. The firewall provides this checking for addresses that are explicitly identified with static command statements. With the change, for inbound traffic, the firewall denies translations for a destined IP address identified as a network or broadcast address.
The firewall does not apply PAT to all ICMP message types; it only applies PAT ICMP echo and echo-reply packets (types 8 and 0). Specifically, only ICMP echo or echo-reply packets create a PAT xlate. So, when the other ICMP messages types are dropped, this message is generated.
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Not a terribly helpful message without more information on your config.
Cheers,
Tim