Foreman-node ENC data error Precondition failed

ENC data for a specific Node cannot be gathered (for salt or simple viewing).

$ /usr/bin/foreman-node
Couldn't retrieve ENC data: Error retrieving node somehost.fqdn: Net::HTTPPreconditionFailed
Check Foreman's /var/log/foreman/production.log for more information.

Happens with the URL, (i.e. salt/node/somehost.fqdn?format=yml) or the legacy GUI option too.
Strangely enough, other hosts can generate/display ENC data.

Expected outcome:
ENC data is displayed.

Foreman and Proxy versions:
Foreman and Proxy plugin versions:
Distribution and version:
AlmaLinux 9.4
Other relevant data:

2024-06-11T13:49:53 [I|app|db4a4f68] Started GET "/salt/node/somehost.fqdn?format=yml" for at 2024-06-11 13:49:53 +0000
2024-06-11T13:49:53 [I|app|db4a4f68] Processing by ForemanSalt::MinionsController#node as YML
2024-06-11T13:49:53 [I|app|db4a4f68]   Parameters: {"id"=>"somehost.fqdn"}
2024-06-11T13:49:53 [W|app|db4a4f68] No SSL cert with CN supplied - request from 10.xx.xx.xx
2024-06-11T13:49:53 [W|app|db4a4f68] Failed to generate external nodes for somehost with no implicit conversion of Array into Hash
2024-06-11T13:49:53 [I|app|db4a4f68]   Rendered text template (Duration: 0.0ms | Allocations: 1)
2024-06-11T13:49:53 [I|app|db4a4f68] Completed 412 Precondition Failed in 58ms (Views: 0.2ms | ActiveRecord: 11.4ms | Allocations: 43204)

nothing more can be found in the logs, what ever the precondition is, I have no clue.

The difference between hosts that work and the one problematic seems to be this

2024-06-12T06:00:38 [W|app|3318495e] Failed to generate external nodes for somehost.fqdn with no implicit conversion of Array into Hash

… even switching Foreman to debug logging does not give more information.
So, a little help or insight appreciated here.

(Note, I tagged this as “salt” since this my config-management system, but maybe this is unrelated to the salt plugins.)

nevermind, seems like we managed to botch up our variable overrides which lead to non-matching types