The 21-year old from Beaudesert has been playing for the Burleigh Bears after being introduced to the Bears in 2019 by co-captain of the Titans, Jamal Fogarty.
Fuller and Campbell share a history of playing together after dominating the under 20's competition for Burleigh in 2019 and will reunite again under Justin Holbrook.
Campbell was quick to heap his praises on Fuller and is ecstatic to be playing together again.
"Honestly, Shal is one of the best young talents I have ever played with," Campbell said.
"He is a freakish footballer. He is just a natural football player.
"I scored 24 tries in 2019 for the Burleigh Bears Colts and he set up about 20 of my tries.
"Shal reminds me of my dad. He is quick off his feet, he is fast and he is just a freak. He can be a star in the NRL.
"It would be awesome for him to stay at the Titans for a long time. I’ve signed my new deal (until 2024) and I was telling Shal to sign as well because I would love for us to link-up again playing NRL for the Titans."
The 21-year old played in seven games for the Burleigh Bears this season, amassing 10 try assists and four tries himself.
Burleigh CEO Damian Driscoll said the club was excited to see Fuller take the next step to the NRL.
"Shallin came here in 2019 from Beaudesert with some help from Jamal Fogarty," Driscoll said.
"He carved up that under-20s competition with Jayden then played A-grade last year and kept improving. He has continued to improve in the Intrust Super Cup this year under Rick’s (Stone, coach) guidance.
"We are really happy. You love to see those guys rewarded and he certainly deserves it. His try-assists and line break assists statistics are very impressive.
"Winning premierships is what we want to do but when you see players like Shallin come into your system and develop it gives you a real thrill.
"Shallin and Jayden in that 2019 team were freakish. They do things that others can’t do and that makes them special."