It is an uncertain time for Garratt but he is upbeat as he edges closer to full health.
"I'm feeling good," Garratt told The Yorkshire Post. "I know it can be easy to overreact to everything but the thing is I feel absolutely fine.
"If I'm just relaxing at home or doing light activity, I have absolutely no symptoms. I'm just not up to full training or a full game of rugby yet.
"The encouraging thing is when I am doing nothing I've got no symptoms so I haven't got any lasting head trauma or anything like that.
"The expert and (club doctor) Gemma (Phillips) are both confident I'm going to make a full recovery and have seen lads come back from worse."
While Garratt can see light at the end of the tunnel, it has not been a straightforward recovery.
The club believe the injury could be traced back to the Challenge Cup tie against Leigh Centurions in late March.
"It's not presenting itself like a normal concussion," explained Garratt.
"It hasn't been since the first week or two. I just get what feels like a change of pressure in my head - a head rush and dizziness.
"With hindsight, we've got a suspicion that I might have had some issues with brain inflammation before the game (against Warrington).
"I didn't come back on against Leigh the week before because Gemma withdrew me for dizziness. That cleared itself up during the week.
"During the game against Warrington, we don't think it was the incident when I was knocked out after an unfortunate clash of heads with Frankie (Halton). I had a number of high collisions leading up to that point which we reckon caused more of the damage.
"The first week after that it did present itself like a concussion. I was struggling with light, sound and clarity of thinking and short-term memory.
"After a week or two, that seemed to come back and I'm back to normal with that now."
The Robins broke new ground at the end of last year when they welcomed Brianna Mulhern to the club to undertake concussion research as part of the backroom team.
Garratt is grateful for Mulhern's unseen work behind the scenes.
"The reason we knew about the high collisions before the knockout incident is because of the GPS in the back of our shirts," said Garratt.
"Because Brianna was there, we've had access to that data which can help us diagnose and treat the symptoms, and determine the cause of the symptoms after the incident.
"One hundred per cent it's definitely been a benefit not only to me but other lads going forward if anything like this happens to them."
Garratt is due to travel down to London to see a second specialist on May 10, when he will hope to get the all-clear to return to action.
But regardless of the outcome of the appointment, Garratt will resist the urge to rush back.
"I'm going to take my time so there are no lasting effects not just for this season or the rest of my career but whatever happens after rugby as well," he said.
"It could be a week or two after the appointment with the specialist or it could be three to four weeks.
"The most frustrating thing is not even training. It's like watching your mates play out all the time but your mum has grounded you.
"It's probably more frustrating because there isn't a timeframe on it like someone like Mikey (Lewis) who knows it's six to eight weeks. The uncertainty of how long you're going to be sidelined for can be frustrating.
"Early on after two or three weeks I was still getting some symptoms and what can be frustrating is the uncertainty over the permanence of your symptoms. You hear all sorts of horror stories about people having to retire."
Former Hull KR player Andrew Heffernan played his last game aged 23, while Stevie Ward's struggles transcended the sport.
But Garratt - an impressive performer since joining Rovers from Dewsbury Rams - is not allowing previous cases to play on his mind.
"What's happened to them you wouldn't wish on your worst enemy," he added.
"But you can't think like that. The fact I've got no symptoms most of the time and still have full clarity of mind is the most reassuring thing for me.
"I do know I'll be back. Whether it's sooner or later, that's just the frustrating bit.
"In my head, I'll be fighting fit for the second half of the season and running through the play-offs as well.
"Once I'm back, I'm more than confident I'll get back to how I was playing or even improving on that."