I have used Cetol & Semco; both are good products. With regards to Cetol not setting, it has to be application in below ambient temperature range or defective product in a new can. How long did you wait between coats before overcoating? I wait 24 hours between coats. I have used Cetol for over 25 years & have never had a problem with it setting. Usually apply 2 coats natural followed by 2 coats gloss; overcoat at 24 hours to eliminate need for sanding between coats. I use Cetol on deck mounted handrails. Usually lasts 4-5 years in our semi tropical climate.
I use Semco on my cockpit teak seating surfaces for two reasons; first, I don’t want a slippery surface in the cockpit working area and second, too much surface area to sand / reprep for reapplication. Semco, is a different animal. Goes on like water & penetrates into the teak. Very minimal prep & easy application. Three coats usually lasts only one year. It seals & protects the teak & dries to a dull finish. IMHO, does not look as good as Cetol; you are not going to achieve a bright glossy finish using Semco.
