Dropdown listing related objects in subpanel

I am currently facing the following situation

A [Company] can have multiple [Funds]. A [Deal] can have multiple Bidder [Company]s. A [Company] can also be involved in multiple [Deal]s as a Bidder.

Therefore, n to n relationships are able to be formed and looked through in subpanels.
In one subpanel of the module [Deal], the user can add multiple [Company]s as Bidders.

What I want to do now, is to let the user decide which [Fund] of which [Company] was used for a [Deal]
Naturally a [Deal] can also therefore have multiple [Fund]s used by Companies.

Instead of setting up two subpanels, I thought about the idea to have a dropdown box do the job, such that for each involved bidder I am able to screen through all of a [Company]'s funds and then chose the right one (but only one for a deal-bidder-pair). This should be able for each row in the subpanel.

Is this technically possible at all? are there at least good resources in order to set up dropdown boxes in a subpanel’s record? …or at least resources that explain how to manipulate a subpanel and its columns in a similar fashion as it would be possible ListViews and logic hooks?

Thanks in advance.