A/C sealers....BS?

Got a leak in my work truck A/C. Garage says they dont work on them anymore due to EPA license. I lose about 20 psi in 2 weeks. I usually see 55-60 psi when it's running and when I measure it after 2 weeks it's down to 40-45 and the compressor is cycling. I squirted all the unions I could see and none bubbled. I had a leaking high side Schrader valve but I fixed that so I'm thinking it's in the compressor or condenser. Maybe a can of pressurized sealer or a non pressurized injectable sealer? 2002 Silverado 2500HD.