Foreman is a Ruby on Rails app, you can migrate database via foreman-rake db:migrate, see our upgrade guide how to do that properly during upgrades - our RPM package does this automatically for example.
Yes, several. I will mention Red Hat Satellite 6 because I work for Red Hat, but there are few others and also individuals/consultants who can provide you commercial support. We don’t have any category in the forums for commercial inquiries tho, feel free to create new post in the Support section with proper title asking for this kind of service and I believe you should find some offers in your email.
Foreman 1.9 is very old - over 3 years old. Our upstream policy is only to support the latest 2 version of Foreman, which is currently 1.18 and 1.19. I would strongly urge you to push for a newer version of Foreman - you may wish to browse the list of security bugs as many will affect 1.9 but not patched until a later version
There are ways to upgrade the database to the the next version, but downgrading in the case of a rollback is not tested. It should work, but there may be dragons.
Additionally, given you had difficulties in upgrading (which is generally tested), I should probably remind you that upgrades should be done in order (i.e. 1.9 ->1.10 -> 1.11 etc) - jumping to the latest version directly is unsupported and probably going to break over such a large jump.