I would roll on the same day after working out, which is followed by consecutive off days.
For example if Thursday is your last workout day of the week, you'll have all F-Sat-Sun to recover.
If you have a hard weight training session the day after rolling, it might be hard to keep up with the same strength and focus you would normally have. A high enough MDMA dose will leave you depleted mentally and physically the next day.
Plus, if you take any pre workout supplements with caffeine, they won't have the strongest effect on your body if you just rolled (the stimulation aspect they provide).