Based on the information provided in the context, the hold status of a location is determined using all the hold policies applied on that location and the distribution status. The hold status of any successfully applied hold is applied. If a location is part of multiple hold policies and some of them have a Failed/error hold status, the hold status of the location would be Not on Hold. Therefore, it is possible that the hold status indicates "not on hold" for some custodians if there are failed holds on their data sources.
Regarding the issue with custodians not seeing the case related to them, it is recommended to verify that the custodians were added correctly to the case and that the hold was placed successfully. If the issue persists, it may be necessary to contact Microsoft support for further assistance.
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