[2019] How is the pet chance for Dojo Mojo calculated with Anachronia?

For agility courses the following formula is used.

• Chance per lap = Ticks to do the course x Level/Virtual Level / 50,000,000

Meaning someone doing the Prif agility course (70 ticks) with 120 Agility has a 1/5,952 chance to get the pet.

However what is the tick number for Anachronia? If we assume its the fastest known time (5:10.2 which is 517 ticks) it is 1/806 but if we take the "achievement time" of 7 minutes it becomes 1/595