That’s a developer question, not an end user one, although I suppose you could hack it together with the conference application. These are end user forums. Really you need to use audiohooks.
Also using a tone in the middle of the speech range seems a strange choice. Such tones would normally be CTCSS ones, which are typically below the normal telephony range (maximum 250.3Hz), although they may get through if the system is purely digital or baseband. Note that only simple codecs are likely to reproduce low level pure tones well, as they are not speech like.
(It does seem that Motorola do use 2175Hz guard tones, although the protocol also involves the same tone at high level. http://www.repeater-builder.com/motorola/msf/pdf/MSFUHF12ToneRmt.pdf)