What you call TD-COMPANY-NAME is usually called SenderId or Source . We support it in all our API calls .
For example, this query:
curl -X "POST" https://api.wavecell.com/sms/v1/amazing_hq/single \ -u amazing:1234512345 \ -H "Content-Type: application/json" \ -d $'{ "source": "AmazingDev", "destination": "+6512345678", "text": "Hello, World!" }'
Results in: 
As for the second part of your question, I see no problems using several different sources, until all of them are irreconcilable and authentic (do not try to imitate other trademarks).
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