help with Slicer and Relationship mess

So I have a bit of an issue getting my slicers to work...

On one particular graph, I have Bookings vs Forecast. They are in different tables. The axis is from a Master Date source that formats the dates how I need them to look (some values are monthly, weekly, daily). There is a 4th table that is in play here which is where I am running into the problems. It contains Master Data (classification, stocking strategy, origin, end location, lead time, etc.). When I go to make the relationships I cannot link them together the way I need to.

Forecast connects to Master Date. Bookings connects to Master Date. But I can't get Master Data to connect to both Bookings and Forecast at the same time. I've tried duplicating, merging, appending, but nothing seems to work.

Is there a way to set-up a slicer that effects two different table without being related to them?

Ask questions if this makes no sense. I can provide screenshots in a bit if that would be helpful.

Thanks!