Cannot use from_dataset() with join criteria on capitalized field name

I must have been fatigued when I posted this because it looks like I put the field() wrapper on the wrong end of the hash key/value pair. Part of my confusion is that I learned in other posts that the right-hand side should not be quoted.

So it should be like this?

from_dataset("Eligibility", "Id", "MemberId" => field('MemberId'))

So the colon is also replaced by the arrow operator in this call to from_dataset() ?