I don’t understand why you would at all consider employment anywhere near your current income that also involves giving up your side project for ??? reasons. Let alone for less.
Revenue sharing is what you do with business partners. In any partnership, you need to have a lawyer review the contract to limit the ways your partners could cheat you. Becoming business partners while also being an employee is unconventional. You will have a giant conflict of interest. They are a big company. Some director will have control over your side business and may someday cancel it without warning. Then your revenue sharing will be worth nothing and you will hate your job.
However, they supply dealflow and they will work on your behalf.
If your numbers are as described you may have acquisition opportunity better than what your being presented now.
You will be given a solid idea of estimated value well in advance of meeting anyone, and are not obligated to sell at all.
I sold a side project using a broker last year and was pleased with the outcome.
If you have questions feel free to contact me.