Hi
Yes, that is correct.
The MOH from TMU cannot be used in RACEI command for extension (RACEI

IR=...,WELCOM=...,CONT=...

Here is the extract from Alex
[tt]CONT= D 1 D 2 D 3
D 1 D 2 D 3 = 0 Signifies that no continuous announcement is to be provided.
1-250 Announcement number, 1 - 250.
251 Tone Message, Music on hold input One.
252 Tone Message, Music on hold input Two.
253 Tone Message, Music on hold input Three.
254 Silence, No Announcement, No tone Message.
Note: CONT parameter values above 250 (tone message, MoH) is applicable only for groups and not individual extensions.
[/tt]
Best regards