Suing my landlord in NY Sm Clms Ct for unreasonably denying my request to sublet. Landlrd's atty says I can't sue. Seeks $2500 legal fees. Who is rt?

I am a rent stabilized tenant, 38 years on my lease. Asked landlord for permission to sublet my room for 2 months. Satisfied landlord's sublet application, but landlord kept adding requirements, making it too burdensome, so landlord, imo, unreasonably rejected request to sublet. Suing in Small Claims Court for loss of 2 month's rent on Aug. 15. Landlord called me yesterday to say would seek legal fees. Their attorney claims I don't have the right to sue in this case under NY RPL 226-b and is seeking at least $2500 in legal fees. They claim my only remedy is release from the lease. I see that this is true for an assignment of the lease, but I don't see it for denial to sublet. To me this is really about harassment and trying to get me out of the building to raise the rent. Seeking advice.