In that trade Roy Hawes was sent to Miami in 1956...but he only stayed for 5 games before heading to Charleston in the Detroit system.
The Lincoln Star of July 31, 1956 has this story:
"CHARLESTON. W. Va., - Purchase of outfielder Roy Hawes from Miami of the International League was announced Monday (ed.-July 30, 1956) by the Charleston Senators. Hawes, 27-year-old lefthander, batted .311 with Louisville of the American Assn. before being traded recently to Miami.”
Hawes stayed with Charleston through the start of the 1957 season, when he went to the Braves' system. That deal is outlined here in this Mason City Globe Gazette article from May 11, 1957:
“DETROIT (UP) -- The Detroit Tigers added left handed strength to the bullpen Friday by bringing up southpaw Lou Sleater from their Charleston farm club and releasing Pete Wojey outright to Charleston. The Tigers obtained Sleater Monday in a minor league trade that sent outfielder Roy Hawes' to Milwaukee's Wichita club.”
The "Monday" in question would be May 6, 1957. Lou Sleater's Baseball Reference major league page has the following listed for this deal:
April 11, 1957: Released by the Milwaukee Braves.
April 20, 1957: Signed as a Free Agent with the Detroit Tigers. (Date given is approximate. Exact date is uncertain.)
So that looks off by quite a bit.
Hawes went to the Dodgers' system in 1958, but I have not been able to track that one down yet.
I DID find this nugget from the Miami News of Jan. 30, 1957 , an article talking about how tough it was for the Marlins to get their roster together for that season, quoting Marlins GM Eddie Stumpf:
“Detroit owes us a Triple-A player off the deal in which they bought outfielder Roy Hawes from us last summer…”
So maybe add a PTBNL to that deal, but I couldn't find where anyone was sent to complete it.