How to see if a record exists in another table with criteria from columns in another table?

[cnussbaum]

I have three columns in Table A:

• a person's name (lookup of Table B)
• a person's role (lookup of Table C)
• a posted message (lookup of Table D)

For some reason, my posted message column blanked out (Don't ask. I have no idea how.) So, I'd like to see if there is a way I can reconnect the lookup of Table D automatically without using an API. Or is there a way I can build another column in Table A that will return the record I need to reconnect (based on the matching criteria of name (table B) + role (table C))?

[TheTimeSavingCo]

What's the primary field value of Table D?  If it's "name (table B) + role (table C)", you could try creating a formula field that outputs that text and pasting that value into a linked field to Table D?

Could you provide some screenshots of the relevant tables?