Does jainsm forbid two souls from meeting in heaven strictest answer possible no or yes
No.
In Jainism, there is no rule forbidding two souls from meeting in a celestial realm. Souls can be born in the same heavenly abode if their karmas lead them there.
But one important point: heaven is not liberation in Jainism. It is only a temporary birth in a higher realm; the soul still remains bound by karma.