Phone conversation diarization with LIUM
system.Telephone is just for detection of speech, that's why you get only init clusters.  You can use default fr.lium.spkDiarization.system.Diarization it will do proper steps as described in LIUM docs, result will be like this:

;; cluster S0
file 1 0 1135 M S U S0
file 1 5722 300 M S U S0
file 1 9266 359 M S U S0
file 1 12670 370 M S U S0
;; cluster S1
file 1 1135 832 F S U S1
file 1 5372 350 F S U S1
file 1 6022 572 F S U S1
file 1 10167 1550 F S U S1
file 1 13040 466 F S U S1
file 1 13623 352 F S U S1
;; cluster S10 [ merge HCLR 0 = S10 in S11 with 1.208107727685253 ]
file 1 1967 693 F S U S10
file 1 2660 1644 F S U S10
file 1 4304 1068 F S U S10
file 1 6594 937 F S U S10
;; cluster S12
file 1 7531 429 F S U S12
file 1 8692 574 F S U S12
;; cluster S13
file 1 7960 732 M T U S13
;; cluster S16
file 1 9625 542 F S U S16
file 1 11717 953 F S U S16


LIUM models included into jar are trained for 16khz, so the input should be better 16khz, you need to resample your 48khz file to 16khz before you feed into LIUM.

If you want to run on telephone speech, you might need to retrain mail/female/ubm models for that. It is also worth to note that LIUM models are trained for French, for other languages they should be better retrained.

Overall, LIUM is not expected to work out of box, you might need to spend some time to make it work properly.