Hi Michal,
I have used the following script on multiple occasions when I had similar issues:
Resetting and running the Service Manager Data Warehouse Jobs separately
https://sarbulescu1.rssing.com/chan-4505354/article49.html
Some other helpful links on Troubleshooting the SCSM Data Warehouse:
DWMaintenance Stalled Processes Kill the SCSM 2012 Data Warehouse
https://dougsigmon.wordpress.com/2012/09/20/dwmaintenance-stalled-processes-kill-the-scsm-2012-data-warehouse/
and also, the part "Management packs are stuck in Pending Association status after registering to the data warehouse" from:
Microsoft.SystemCenter.Datawarehouse.OLAP.Base is in the pending association state
https://www.scutils.com/blog/scutils-blog/system-center-2012-service-manager/microsoft-systemcenter-datawarehouse-olap-base-is-in-the-pending-association-state
Please do let me know if this helped out. Thanks in advance and Regards,
If my reply was helpful please don't forget to upvote and/or accept as answer, thank you!
Regards,
Stoyan