Unironically they will point to the fact that he's in Russia, not counting the fact that he was travelling to Ecuador and had his passport revoked while enroute and the US was intercepting planes coming out of Russia (even of diplomats).

https://en.wikipedia.org/wiki/Evo_Morales_grounding_incident

I think the evidence is basically:

1. He was a spy

2. He now lives in Russia