Logged a case with Solarwinds support and got a fix.
In NCM 7.4., there is a new command <Command Name="UseExactPromptMatch" Value="true"/>
The revised template is:
<!-- edited with XML Spy v4.4 U (http://www.xmlspy.com) by () -->
<!--SolarWinds Network Management Tools-->
<!--Copyright 2005 SolarWinds.Net All rights reserved-->
<Configuration-Management Device="Sierra Wireless" SystemOID="1.3.6.1.4.1.20542">
<Commands>
<Command Name="RESET" Value=""/>
<Command Name="MenuBased" Value="false"/>
<Command Name="DownloadConfig" Value="AT&V"/>
<Command Name="Version" Value="ATI1"/>
<Command Name="Reboot" Value="ATZ${CRLF}"/>
<Command Name="VirtualPrompt" Value="OK"/>
<Command Name="UseExactPromptMatch" Value="true"/>
</Commands>
</Configuration-Management>