Similar experience
Had a similar RA ("descend, descend") on the ILS at an African airport. The PNF remained on the glide slope descending at approx 1000 fpm. Also in VMC conditions but without the continuous ATC chatter you experienced. I have used 121.5 on the No.2 VHF to speak to tower during a critical time when the main freq was blocked.
Like you, very grateful it was day VMC when it happened.
Cheers CK