Hi @klngroup , I’m Amruta from SureForms team. 
I’ve reviewed the support ticket you had raised and the complete thread thereafter.
First and foremost, thank you for sharing all the details from time to time and also being patient as we looked through the issue.
I know there hasn’t been much luck from reaching out to caching plugin support. I’d like to kindly request you to try another caching plugin once and see it that fixes the issue. We’re positive this will help you overcome your issue. Our team is eager to help, so please do give it a try once and feel free to reach out if the issue still persists.
In the meantime, please know we will also continue to keep an eye out for any dependency that may be causing this issue. We are continuously working on improving SureForms to provide compatibilities for different caching mechanism.
Looking forward to hearing back! Hope you have a great day ahead 🙂
Best regards!