Tulo probably needs to stay in the AL. Even his 2015 and 2016 weren't that great offensively, though obviously good for a SS (his defensive WAR was actually still pretty good, but hard to think that would still be the case). Doesn't get on base and who knows where the power will be at this point. Also hasn't ever really played 3B.
The Machado situation seems pretty simple to me. The Yankees, if they really want him, are going to offer him $350 million. How high do you go if you are the Phillies to beat that? 370 is okay by me. What if the Yankees come back at 380? At some point, it is okay to walk away. You can also make the case for giving him 400 (especially if they truly have to both outbid the Yankees and get him to play 3B).
But it wouldn't be good franchise management to just offer him 400 and try to be done with it tomorrow if you still might be able to get him for $360 (or get Harper for 350). He still wants to do his circuit anyway. And Harper is still gonna be here in January. Machado might too.
It will not be great if they land neither player but it still really depends what back-up plans are executed if that's the case. Or what needs to be done now because it will go away before they sign.
Regardless, everyone will shut up about it if the team actually wins. Manny is the best way to add 5-7 WAR in a single move and Harper is probably the second-best (though his 2018 numbers don't say that) but another OF and 3B (or one of those things and a catching move) will do it too.