Commercial Floor Drain Disaster

This is my floor drain disaster
I am completely frustrated with floor drains at a local restaurant. There are four large stainless steel floor drains in the kitchen of a restaurant with a parking garage below. The cut outs in the slab are approx 2'x2'. The floor drains have a 3" discharge and the lip of the drains overlap the concrete roughly 0.5-1". The floor in the kitchen was epoxy at one point but now is pitted down into the concrete. My company removed the drains at 11 PM cleaned the surfaces poured a few gallons of epoxy under the drains lips and over the edges and dropped the drains back down. The drains are solid, you can jump on them and they don't move. Below in the parking garage there are two steel bars going across for emergency support. We finished the job at 7 am. Shortly after the cleaning crew started messing with the kitchen and disturbed the sealant. The restaurant dumps 40 gallon pots of boiling water into the drains on a regular basis, it appears to have warped one of the PVC pipes. But not the problem I care about. Our seal job worked well for about 3 months, now the problem is back. The problem is that water from the floor is seeping between the floor drain and the concrete and making its way to the parking garage. I thought of a few ideas but do not feel confident in them.

1. Repour expoxy floor and overlap over stainless: cons= may not stick to stainless, may peel back off edge, boiling water may soften, we only have 8 hours to complete work
2. Put double side tar tape under lip of flange, drill 8 holes in each of the stainless steel drains. Fasten/anchor to floor. Use some type of cement or fast drying epoxy on floor around drains. Cons: Hot water may degrade tar over time or not seal at all.
3. Insall some type of flashing over edges of drain


Any suggestions would be greatly appreciated