The two women are believed to have met each other at an indigenous smoking ceremony held at Dreamworld just weeks after the disaster.
A source told the Sunday Mail the two had formed a "genuine friendship."
"It’s a very genuine friendship and it’s probably one of the only nice things that has come out of all this," the source said.
"'They really do care for each other and they both lament the loss of those four lives."
Dorsett and Thomas are reported to have spent time at Ms Thomas' holiday home and regularly speak to each other on the phone, a friend of the women told the Sunday Mail.
A formal inquest into the Dreamworld tragedy started in June, with ride supervisors and engineers working at the park giving their testimonies.
Senior park managers including those in charge of engineering, maintenance and policy spoke at the second part of the inquest held in October.
The coroner will announce the findings from the inquest early next year.