The RD is still deeply in debt.
Who needs tourism revenues, if they were arriving , right?
Slap them in the face, so they will not return.
Britain has a good relationship with the US, but if a British national goes to the US on a tourist visa and overstays, the US government deports them and the same is true the other way around. Applying immigration law doesn't sour international relations. If the DR were to deport those who overstayed, don't think any foreign government would bat an eyelid.