Gosh, that's silly. What is "farfetched" is to claim that Grammar just fabricated his account. I swear I hope none of you lone-gunman believers ever works in law enforcement, because you would never catch anyone.
The Western Union money order was clearly an attempt by Ruby to make his hit on Oswald seem like a spontaneous, compulsive act. Even the HSCA did not buy it.
If Ruby had waltzed into the basement the way the WC said he did, via the Main Street ramp, the spontaneous-act story would have a tiny bit of credibility, which of course is why the WC claimed, against all the evidence, that Ruby entered via the Main Street ramp.
But we know that's not how Ruby got into the basement. He entered via the circuitous route of taking the alley next to the Dallas Municipal Building and then using the stairway that led to the basement from that alley. And, conveniently enough, the door to the stairway was unlocked, and the entrance way at the bottom of that stairway suddenly became unguarded shortly before Ruby used it to enter the basement.
Several impertinent questions:
-- Is there proof that a door to the Dallas Municipal Building (adjacent to the alley) was unlocked on Sunday morning, 24 November 1963?
-- Has it ever been determined how long it would take Jack Ruby to get from the Western Union to the bottom of the Main Street ramp via the alley > Dallas Municipal Building hallway > stairway to the basement?
The time-stamped receipt Ruby received at the Western Union was for 11:17 AM. The shooting of Oswald was at 11.21 AM. Could Ruby have made the journey in less than 4 minutes?