Hi @Anonymous ,
According to my test, I find that your second workaround( reference "cdm_workerid" putting a dot "." after cdm_Workerid ) is great, the look up field can be filtered as excepted. Though you cannot click it on in the collection page, actually you can call it in powerapps.
Please refer to my following test:
The left table in below screenshot show a entity(reservations) with look up field (Product reservation), the button create a collection(AA3) with filter function, and the right table show that collection which is filtered by the look up field. Also I put a label to show the look up field value of Collection.
Here is the formulas:
Button Onselect property:
ClearCollect(AA3,Filter(reservations,'Product Reservation'.Name="Laptop"))
Label Text property:
First(AA3).'Product Reservation'.Name
The Text property of two lookup field in Table should be modify from ThisItem.'Product Reservation' to ThisItem.'Product Reservation'.Name

So as you can seen ,the filter function is effective for look up field.
Best regards,
Sik